I Think Faster Than Light Travel is Possible. Here's Why.

Try out my quantum mechanics course (and many others on math and science) on Brilliant using the link brilliant.org/sabine. You can get started for free, and the first 200 will get 20% off the annual premium subscription.
Take the quiz to see if you understood everything: quizwithit.com/start_thequiz/...
If you've been following my channel for a really long time, you might remember that some years ago I made a video about whether faster-than-light travel is possible. I was trying to explain why the arguments saying it's impossible are inconclusive and we shouldn't throw out the possibility too quickly, but I'm afraid I didn't make my case very well. This video is a second attempt. Hopefully this time it'll come across more clearly!
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00:00 Intro
01:51 The Speed of Light as Limit
06:12 The Speed of Light as Barrier
12:44 Time Travel Paradoxes
20:47 Quantum Gravity and Summary
21:54 Learn Physics on Brilliant
#science #physics

[@SabineHossenfelder]

This video comes with a quiz which you can take here: quizwithit.com/start_thequiz/1687737623494x575496266320185500

[@kh9242]

Darn i missed two "Your score is higher than 22% of the people, who took the quiz! Good job!" I wanted a 100 i have PTSD now heeding to safe space

[@brycering5989]

Plot Twist, Sabine is from the other side of the Milkyway, and is trying to find a suitable mate ;) Hmmm, extraterrestrial extraspecie-al intercource, I think I personally would break the boundaries of C, but would do my best to not let my water hose spit out too soon.

[@RWBHere]

You can think much faster than light already. To prove it, think about our Sun warming the Earth. Now think about the Andromeda Galaxy, as seen through a telescope. You did both of those things in an instant, but sunlight takes over 8 minutes to reach the Earth, and light from Andromeda takes about 2.5 million years to travel to our telescopes.

[@firecat3613]

8/9. I could have gotten 9/9 but, although I knew the answer you wanted, I disagreed with it and a more accurate answer was available. But that's the wonderful thing about science, we don't always have to agree on everything. Often our disagreements can open the doors to new understanding and new advancements, for one of us, for both of us or - in some cases - for all of us.

[@firecat3613]

@@RWBHere The trick is determining what is occurring in the moment. Sure, it's easy to determine that the sun is still shining this very moment. It's not difficult to make an inference from something as recent as 8 minutes ago. But let us not consider Andromeda, but use something much closer as a reference. Imagine a star in our own galaxy. It is 50,000 ly away. We see it clearly with WEBB. The star is an unstable red giant. Is it still there? Is it still a red giant? Is it a white or brown dwarf? What is happening to that star, right now? Now consider Andromeda, a galaxy 50 times further away that that star. What is going on there?

[@robonator2945]

The thing I love about this channel is half the time it doesn't feel like a youtube channel, or even a documentary channel, it just feels like a professor's mid-lecture ramblings that they spend half the class talking about because they're just so damn interested in it they completely lose track of the discussion and if you ask me, those are the best ways to learn.

[@alysdexia]

not plural, dolt

[@Kumagoro42]

I get the general sentiment, but I disagree about these videos feeling like ramblings. They feel meticulously prepared.

[@robonator2945]

@@alysdexia you know rambling can be a noun right dolt? Someone can start rambling, or someone can record a rambling. The noun form is just the conceptual object form of the verb.

[@alysdexia]

@@robonator2945 I said nothing about rambling, you wit/2. But I know that a gerund isn’t a verb.

[@robonator2945]

​@@alysdexia well that's bascially the only plural I used, soooooo. The only other plural I used was "those are the best ways to learn" which is a valid plural since I'm referring to the plural group of rambling *_s_* as a concept and not a single rambling. You could argue that it should represent a single "way" of learning but that point it's completely useless subjectivity and there is no "right" or "wrong" answer and it's just a classification problem. Equally however you could argue that a rambling is just a sub-set of the super-set of "passion inspired tangent from a professor" which can include other sub-sets and as a result wouldn't just be an acceptable plural but a demanded plural.

[@sriharsha5036]

Clicked on this one faster than speed of light.

[@michaelfried3123]

clicking on clickbait gets slow rolled by those of us who know better. this video is for the dummies out there...

[@faeancestor]

man

[@nonsequitor]

In what medium? 😉

[@Lilliathi]

@@michaelfried3123 Oh, I'm sorry superior being who likes his own posts. I bow to you.

[@MrYobII]

Not while your thumb was traveling through a medium

[@nickhartwell6889]

I really appreciate your pause in discussion at around 18 minutes to recap the present topic. You knew right when my head was starting to lag while absorbing this information. Phenomenal teaching.

[@SPQSpartacus]

8:20 You’re almost entirely made of Pure Energy. Though when I see how much time you spend watching KZbin I find that hard to believe. My new favourite quote.

[@SabineHossenfelder]

Hi All, I realized too late I should have added a word about quantum mechanics: Quantum mechanics has the same speed limit (barrier!) as special relativity, and special relativity is where this barrier comes from. Therefore, quantum physics doesn't change anything about what I explained here. (Which is why I forgot to even mention it...)

[@eonasjohn]

Thank you for elaborating.

[@jewelrybag4557]

Why would an advanced civilization use clunky spaceships to visit us? Won't they have perfected nanotechnology or quantum technology to achieve their goals?

[@tomcan48]

Sorry again, if we are looking ONLY at physical manifestations, then YES. But the speed-of-light can easily be exceeded through thought. Even those little Greys use that technology and even our relatives from the constellation, Lyra, which we originate from, use consciousness as the base means ships, similar to what we see on Star Trek. Unfortunately, outside the SSP, we are restricted to consider such things as impossible, due to our programmed viewpoint. Maybe someday we will be able to break through this forced programming.

[@jagpreetbatra5084]

Beautifully explained we need new mathematics to first work out in theory behind Ftl then Do some experimental work

[@eewls]

Thank you for this fantastic philosophy video, Sabine

[@p.a.1675]

“Hey, we don’t serve faster-than-light particles in here.” A tachyon walks into a bar.

[@rajeevgangal542]

He was served beer but didn't drink. Why? Cause he was virtual

[@enriquea.fonolla4495]

that is a very good nerd joke.

[@bradysmith4405]

Did he walk in after because they go back in time?

[@MariosPOS]

lmfaooo

[@rosecodith007]

Are Tachyons related to Klingons? Because if they are, then that is a sure fire recipe for a bar brawl! Tachyons ain't gonna take that, not being served!

[@lobojk]

Sabine, this is fantastic and funny. I'm not sure I could answer any of the quiz questions... but I will watch you again. This presentation is crazy cool.

[@simply-ericcole8201]

Love this channel and Sabine's explanations, even of stuff I already know. Keep up the good work !!

[@onthefive5615]

Not understanding physics has been a drag all my life. For instance, I've been all into plate tectonics theory since the late 60s, and while I seemed to excel at logic, physics was a brick wall halting my ability to explain and argue my reasoning. That brick wall (my thick skull - or being lefthanded -according to teachers and parents) later interfered with my passion for studying oceanography and geology as deeply as I wanted to in the 80s and 90s. So my college degrees were light om math studies. I'm telling you this because watching your videos, the way you describe and explain things led me to discover how physics works. I can now say, at 74 years old, that I get it!!! I'm so grateful, thank you!

[@Levon9404]

You know the good saying, old man, better late than never, finally you can consider you were able achieve something in your life

[@DarkKnight_]

Never stop learning then your curiosity and wonder will never leave you.

[@MichaelJones-rg3hv]

Congrats! Always good to learn new and wonderful things.

[@sunbeam9222]

I experienced the same thing ( and also left handed ;)

[@Levon9404]

@@sunbeam9222 Physics is something, you have to have certain attractions to physical things, to understand how to find key to understand secrets they fundamentally exist and function.

[@Termini_Man]

Thank you for having a full transcript for the close captions. You have no idea how much I appreciate. So many channels don't, so the subtitles aren't accurate, or maybe they don't even have any. I have auditory processing disorder, so I have issues understanding talking sometimes.

[@bazem]

It's also very useful to people who can read in English but are still learning the listening part. It can be hard to follow different accents and speeds while still learning. The subtitles help a lot with understanding the content and also training your ears.

[@alant383]

I just absolutely love the 'simple' way Sabine explains everything and then makes a Segway into the mundane. Just love it! Surprisingly I followed most of everything she said. And I love her accent too :-) Sabine, you make me want to learn more and go back to school to learn something different. And yes, I will sign up for Brilliant (did already) - or was that a time-space loop??

[@xue1379]

Segue

[@RobertTowell]

I do not know why youtube decided to start putting these videos in my feed. But I am loving them. She does an excellent job of explaining things in a way I can follow. Great channel!

[@user-gx1rk8yw6l]

Of course understanding an explanation is no guarantee of the explanation's validity... FYI: Whether Sabine is wright or rong is a totally-different issue.

[@prodiver7]

There was a time-traveller named Wright who travelled much faster than light. He set off one day in a relative way, and arrived on the previous night.

[@audiodead7302]

I just asked ChatGPT to write a limerick about travelling faster than light and time travel. I like yours better!: There once was a physicist quite bright, Who dreamed of a journey through light. With a machine that could time travel too, He set off on an adventure anew. He broke the light barrier with ease, Zipped through the cosmos with such great sleaze. But when he arrived at his destination, He found himself in an odd situation. His time machine had worked too well, And sent him back to a time he couldn't tell. He realized with a start and a fright, That he was stuck in a time-loop of light. So, if you ever think to travel so fast, And attempt to journey through the past, Just remember this limerick quite well, Or you might end up trapped in a time-cell.

[@alextw1488]

the way the rhyme played I thought you might say something that ended in shi-ne a light

[@fairygodmothersdog]

@@audiodead7302 OMG #talesfroma21stcenturyfairygodmother uses through loops to save a place in time and space, but this ai actually touched on a funny notion that eventually all time traveler's get imprisoned and I forget where I read it, a meme or work of sci Fi, but that's so interesting that was generated. "Sleaze" is a bizarre word to use there.

[@fairygodmothersdog]

Prodiver7 I really liked yours. Did you write that?

[@subspaceanomaly]

@@audiodead7302 I would like to go on a sleazy trip across the cosmos

[@tayzonday]

Isn’t speed always infinite from the perspective of the photon? Like, a photon from the early universe might take 13 billion years to reach us from our viewpoint- but from the photon’s view, the journey is instantaneous. Thus, our perception of “speed” (distance over time) is just an artifact of our motion experience.

[@Zalemones1]

Time is meaningless at the speed of light. The very idea of time passing does not even make sense at the speed of light.

[@robertanderson5092]

Isn't distance also meaningless?

[@VivekPatel-ze6jy]

I think so... Time dilation really messes with my brain lmao

[@Chimwizlet]

As Zalemones1 said, time is meaningless at that point. The misconception comes from the maths which suggests that as speed approaches c the length contraction approaches the point where distance is 0 and so the journey is instant. But that doesn't mean it actually is 0 at c, at that point the equation is no longer valid in the same way 1/x has no value when x=0.

[@jitteryjet7525]

Exactly! Something travelling near the speed of light can cross the known universe almost instantaneously, from their point of view.

[@bombheadgames9565]

The Lorentz transformations for speed, mass and length go totally nutty as v approaches c which is why you cannot travel AT the speed of light because your mass tends to infinity, so the kinetic energy you need also tends to infinity.. However those same formula say once v > c that mass drops sharply back away from infinity.. What this implies is it could be feasible for particles to tunnel from below light speed to above lightspeed, the same way electrons tunnel through impossible voltage gradients in Zenner diodes.

[@TheSourJam]

Just a small correction: as v approaches c, it’s the total energy that tends to infinity, not the mass, as we abandoned the idea of relativistic mass some time ago. The total energy of course just being the kinetic energy plus the energy from the mass (E=mc^2).

[@Henrix1998]

Imaginary energy let's go

[@HuyV]

So we just try to tunnel each of our atoms to FTL until we manage to do that for all of our 10^28 atoms and then try to sync up all of them travelling with different headstarts so they end up in a human shape again? Sounds like a plan

[@TheTonyMcD]

Thank you for covering that supposed ftl time travel paradox. I never understood the argument. I could follow it, but it never made any sense to me how bob's perception of something traveling backwards in time could somehow be used to give his past-self a message. I'd always assumed that I just couldn't grasp what was actually going on, or that I was missing something. You've renewed some confidence in my own intelligence.

[@busteraycan]

To me it seems like if supersonic aircraft don't break causality faster than light space ships also shouldn't. But of course I don't have any formal education on relativity so I always assumed I just wouldn't understand the reasoning without the mathematical groundwork behind it. (tbf I still don't understand why some scientists believe FTL would break causality))

[@imacds]

"if you live in the USA, make that 20" as someone who commutes by train, I felt that.

[@neurofiedyamato8763]

unfortunately true

[@DrorF]

Now I get it. Thanks.

[@GuyFromJupiter]

One of the 5 people here in the States that does!

[@HocusPocus6969]

I spit my coffee on that one. Love it.

[@luke_fabis]

​@@GuyFromJupiter One of the five people who can. Our rail network is in shambles. Forget high speed rail, I just wish we had a rail and trolley network like we had in the mid-1800s up until the automotive industry poisoned this country.

[@MartinBica]

This is the most awesome mixture of super high quality information and super dry super funny humor you can experience in this and all 6 parallel univeses. I love the style of Sabine 🙂

[@johnself6435]

Yes but why is she hot?

[@Justin534]

​@@johnself6435Because of her binding energy!!

[@TestGearJunkie.]

Only 6..? I always thought there were an infinite number..?

[@hudsonreynolds4349]

Love this video. Very exciting to examine the nuances of these assumptions that everybody hears. I would absolutely love to see some physicists talk about these points

[@Paul-li9hq]

This is something that has always fascinated me because I've always wondered if we would even be ABLE to see something that was travelling faster than the speed of light... I read up on the subject as best I could, and explanation goes along the lines of: It wouldn't become scientifically “invisible”, but stationary beings would not be able to see something travelling faster than light because light wouldn't have time to reflect off it and into your eyes.

[@javiej]

This is the best video from Sabine, by far. Telling us her (very innovative) scientific opinion on a polemic subject like "faster than light travel", and doing it in a public KZbin video rather than writing an obscure paper she puts her prestige at risk. So thank you Sabine, only the brave change the world.

[@TheChzoronzon]

Au contraire, writing a serious paper will be the ballsy move... a YT vid is irrelevant crap

[@eekee6034]

Such a paper could never stay obscure for long, I don't think. Basically all the science KZbinrs would jump on it the moment they heard about it. There was a time I would have worried it might not get published, but now I can't imagine it being ignored in the prepublication paper exchange. Maybe if the title or synopsis were poor, but I'm pretty sure Sabine of all people could write those well.

[@berniv7375]

@@TheChzoronzon Few people read a serious paper and in that way the general public remain indifferent to physics. Many people watch KZbin videos and if complex subjects can be explained with clarity and relative simplicity then our collective intelligence is raised.🌱

[@Madrrrrrrrrrrr]

@@TheChzoronzon yep but the theory is not new. The big bang went faster than the speed of light.

[@RobOfTheNorth2001]

@@Madrrrrrrrrrrr space expanded fast than light. Not the matter within it.

[@ericpeterson6520]

This reminds me of my favorite fictional justification for FTL travel, which comes from the book Way Station by Clifford Simak. It boils down to "Humans think that it's impossible to travel faster than light. Turns out they're wrong" And that's it. No further scifi technobabble needed, the "cosmic speed limit" was just an artifact of incomplete physics the whole time and you can just break it (in this universe)

[@onastick2411]

Good read as well.

[@trazyntheinfinite9895]

Funny thing is: we might be wrong. noone knows.

[@alessandrofregoso740]

and it works for unicorns end elves too!

[@defender399]

Speaking of sci-fi and its postulations, I rather like a Doctor Who explanation for apparent aberrations in the space-time continuum. “It’s a wibbly wobbly timey wimey thing.”

[@jamesh1758]

Sort of like how we used to think that heavier than air flight was practically impossible and that birds and insects had some magic or animal science we wouldn’t get. We figured it out for sure, but in a unique way. I suppose the problem is we’ve got 0 examples that this rule can be broken so we think it’s impossible but who’d have guessed we could see inside people’s body’s with x-rays and brains with MRIs before it was discovered.

[@ShannonPopMusic]

To understand the ideas in this video, it may require going back in time in a time loop rewatching this video an infinite number of times.

[@josephnwilson]

“If you wanted to be at rest with the universe you’d have to run at 300 kilometers per second” I sure feel that. Ain’t never fast enough is it.

[@chrisdonnell7200]

POV: you're Sonic The Hedgehog

[@dylanwight5764]

@@chrisdonnell7200 The problem with being faster than light is living in eternal darkness. Sad Sonic noises.

[@scipug3048]

@@dylanwight5764 actually not sure if it does... if you move towards a lightsource at exactly the speed of light, the wavelenth will be squished to 0, which leads to photons with infinite energy... but if you are OVER the speed of light, the wave should just be inverted right? if i turned the light on and off making pauses of: 1sec 2 sec 3sec and 4sec at some exact "over lightspeed"-speed you would recieve: 4sec 3sec 2sec 1sec pauses. in the same way the interval between wave peaks should change from 1ns below lightspeed, 0ns at lightspeed, to 1ns again just in the oposite direction for over lightspeed.

[@ananthan8951]

Don't carry the head for all this. With the bulk unexplored, the space expanding. Have nowhere to go travelling FTL or even supersonically. Metaphysics appears, delusively perhaps, more real. "The manifest universe is a mental construction". Existence - Consciousness is the fundamental reality, all else is dependent reality; appearances in Consciousness. It is that which underlies and pervades wakefulness, dream and deep sleep (and like states of experience of absence).

[@michaellowe3665]

Officer, I wasn't speeding. I was attempting to reduce my speed relative to the universe.

[@sciverzero8197]

Thank you Sabine for giving a name, the co-moving frame, to the concept I've been trying to explain to someone for a long time.

[@captainoates7236]

Wondering if it's got anything to do with Mach's theorum which I've seen videos about.

[@reasonerenlightened2456]

There is no use for science if it can not solve the issue of distribution of Wealth and Power among the citizens.

[@snnwstt]

Around 15:00 (the time loop): Incorrect. The perception is NOT the thing. The Sun is not here, but 8 minutes away, Betelgeuse is not here, but far-far away, the fast ship won't be there, it will only be its appearance that will be there, like the Betelgeuse appearance to us, like our Sun appearance to us. So, the slow mo ship won't be able to give a signal to the fast ship, neither can we to Betelgeuse appearance. Making the difference between the appearance and the real thing kill that Hollywoodian paradox, no more esoterism required.

[@deydraniasmith615]

And traveling to Betelgeuse wouldn't be possible even at faster than light speed. As you get closer, it'll begin to move closer to its actual position and then, when you get closer still, it'll very likely explode in a super nova and become a nebula.

[@CloudPeopleRecords]

I prefer the interview format but 100% respect your forays in science.

[@spoiler321]

I'm always amazed at how slow the speed of light is

[@edcunion]

Certainly to us sub light speed observers, but from its view it travels to Andromeda and back, millions of light years, in no time! It orbits black holes and nucleons and can pop out photons when either are disturbed, or capture or absorb them when a photon gets too close?!

[@j7m7f]

It is as meaningfull as saying that you are amazed at how small pi is. C is not small or big. It just is. If you think it is small then you are probably rather amazed at how big YOU are. Or Earth, or Solar system, or Milky Way...

[@ianokay]

Yeah, especially given the size of the universe. It's slow to us just getting from the sun to the earth... let alone anywhere else! It's even slow inter-planetary; slow enough we can notice the slowness just trying to send data from LA to London. It's abysmally and impractically slow. ​ @edcunion @Jarek F

[@kiefermattern917]

@@edcunion The nature of light means it has no rest frame. There is no photon's view.

[@mreese8764]

@@kiefermattern917 For the photond the speed of light is infinite. They are created and destroyed simultaneously. A photon that travel 10 billion light years and is absorbed on an earth based camera, the emission and absorption together are just one instantaneous process happening at the very same location in space. The photon didn't even travel at all. 🤯

[@widnyj5561]

It's the first time I heard the argument about higgs field condensation regarding FTL topic - and presented very clearly with solid hooks to dig deeper around this. Great movie!

[@gregmark1688]

I'm pretty sure " presented very clearly with solid hooks to dig deeper around" describes every one of Dr Hossenfelder's videos

[@natevanderw]

@@gregmark1688 Meh. Most. There is a few videos that I think weren't done well. Like her video on Elon Musk's "Population of Humans are too low video" and her conclusions at the end.

[@oiuyuioiuyuio]

@@gregmark1688 no

[@123Shel12]

Also my first time to hear about Higgs field condensation. I agree with you that Dr. H's explanation was clearly presented! She impresses the daylights out of me!

[@gregmark1688]

@@123Shel12 Me too! I feel kinda sad for all those losers who can't tolerate an intelligent woman and have convince themselves they're smarter than she is or whatever. Misogyny must be a miserable way to be.

[@sergeyromanov5560]

Your explanation of the ship's direction of travel is completely incomprehensible.

[@neilbhatt7771]

The light from the egg hitting the ground gets to you sooner than the light from the intact egg

[@DreamersNights]

I also thought that the stuff times the thing that rotates Quark ninety percent field dynamics force equations conceptual fiddling that, in turn, produces light from the doohicky straight to the central cortex producing oxytocin for this video. You actually explained this very well. Thanks for making such complex mathematics understandable to knuckle-draggers like me. Liked. Subbed. Awesome!

[@wefinishthisnow3883]

That morning condensation analogy was perfect for a layperson like me to understand. Great stuff Sabine!

[@antonystringfellow5152]

I liked that too, though it wasn't quite correct. Hope this won't spoil the anaology as it's generally a good one, but here goes.... If you observe an area of grass or plants that has an object above it, a tree, a roof or whatever, on a morning with dew, you'll notice an absence in that area. This is a clue as to how dew actually forms. When air cools down so much that it can no longer hold all the water vapour, it condenses into mist but mist is not necessary for dew to form. What happens is that opaque media (in this case grass) radiate heat away faster than transparent media (the air). So, grass exposed to the sky loses heat faster than the air around it. During a windless night, all solid surfaces become colder than the surrounding air. The surrounding air may still be warm enough to hold the water vapour but not once it comes into contact with these surfaces. So, the water condenses on these surfaces. Any opaque objects between the grass and the sky prevent the radiated heat escaping into space, so here, the grass loses less heat and may remain dry.

[@londen3547]

Agreed, but I think her analogy might make better case for ether rather than the higgs theory.

[@ambition112]

0:00: 🚀 The possibility of faster-than-light travel and communication is explored in relation to the existence of extraterrestrial life. 3:33: 🚂 The speed of light is constant and cannot be surpassed, requiring infinite energy to reach it. 6:16: 🔬 The theory of relativity allows for faster-than-light travel, but it is difficult to accelerate from a speed slower than light to a speed faster than light. The concept of infinity in physics is often seen as a mathematical artifact, but in this case, it is not. Most of the mass in objects comes from the binding energy of particles, rather than the actual mass of the particles themselves. The remaining mass comes from the Higgs field, which is different from the concept of ether in the 19th century. 9:53: 🌌 The Higgs field condensate and the ether are different in that the Higgs condensate is the same for everyone, while the ether was considered a fluid with different perspectives. 12:49: 🚀 The argument that traveling faster than the speed of light would cause time travel paradoxes is not technically correct. 15:47: ! The argument against faster-than-light travel causing time paradoxes is flawed in the context of general relativity. 18:56: 🚀 Traveling faster than the speed of light does not necessarily imply time travel, and physicists should consider the possibility further. 22:11: 📚 Passively watching KZbin videos won't get you far, but actively engaging with Brilliant's interactive courses on science and math can help you learn and understand complex concepts. Recap by Tammy AI

[@101perspective]

16:37... Isn't her time diagram flawed anyway? She shows the first traveler flying on a negative slope. For that to happen they would have to travel faster than infinity... right? I mean, infinite speed (instantaneous) speed would be a line parallel with the X axis. Or do I have that wrong? If that is correct then the information would get to the other ship in zero time... then that ship would bring the info back in zero time. Meaning it wouldn't arrive in the past but at the same time you sent it... assuming there is no transmission delay.

[@Patatmetmayo]

@@101perspective From an outside observer's perspective the speed is not infinite, the speed is actually the same as the speed of light when the line is parallel with the X axis. So the one in the ship flying at that speed will feel like zero time has past until they arrive at the other ship, while for the other ship it took as much time for the ship to arrive as normal light would travelling that distance.

[@kakistocracyusa]

How about 22 minutes of vague, hand-waving flim-flam using diagrams from a sophomore-level modern physics course.

[@MrConformation]

Light speed cannot be surpassed? ........Only on the grounds as we limited humans think we know.

[@kakistocracyusa]

@@MrConformation We gotta keep this stupid UFO hoax alive, physics be damned.

[@mikecronis]

I like how various perturbations are included in some of these examples. I think there might be some solutions by including "the reality" of them as opposed to "perfect vacuum" situations.

[@thomascorbett2936]

You should write a paper on faster than the speed of light , maybe some brilliant person will understand and give you a big prize .

[@kraahk1928]

I'm German, so arguably I may not be adequately fit to make any judgement in these regards...but within my personal frame of reference, the amount and quality of jokes in this video was beyond outstanding. Making it both more digestible for amateurs and more funny for (semi -)professionals. Awesome job and thanks. :)

[@mirage4014]

As an English Man living in Germany! It's the first time I realised German people have a sense of humour 😂 Sorry just joking! Sabine is wonderful

[@gottrekk5798]

I am not German but I think in the last 100 years Germans made more scientific discoveries then all other nations combine.

[@creos42]

I'm from the US and love her humor. German ancestry may be to blame though

[@waen606]

I'm only part German ...its hard to know what I can say confidently and what I can't...

[@jimstewart3017]

As the old Beck's beer commercial goes, German's don't comedy, they do beer. kzbin.info/www/bejne/rqi7nZmqa9mCp5I

[@fffffplayer1]

Could you elaborate on how General Relativity and a Co-Moving Frame eliminates the closed loop? I feel like this is the main point to showing FTL could be possible, but you went over it really quickly. I think we'd really benefit from understanding how that transition works, rather than just being told it works. Also, could you explain why the Co-Moving Frame can only be defined in GR? Couldn't we just measure the average velocity of all stuff without gravity, too? I feel like this was a good video for introducing the problem, but a second video to give more time to providing the answer would be very useful.

[@YuraL88]

I think that closed loops can exist, you can even imagine some "universe" that lives in such a closed loop.

[@anywallsocket]

This is all half-cooked theory, built up from isolated models. Ironically she's using these to argue against the half-cooked nature of SM+QM

[@Duiker36]

They don't eliminate the closed loop. They make it reasonable to say there wouldn't be one. The closed loop itself is merely a reasonable conclusion to draw from special relativity, so that's the standard of argument she's aiming to meet.

[@danielbronsky]

I'm not at all educated in physics, so apologies for any mistakes, and take this with a grain of salt... but here's how I've heard it explained: According to Theory of Relativity, if events A and B are causally disconnected, they don't have a "true" order. Depending on your frame of reference, A may occur before B, or B before A, or they may occur simultaneously. Whether or not events are causally connected depends on the distance between them and the speed of light. For example, if you see two buttons, that are 1 light second apart, and then you see them pressed simultaneously, then they are causally disconnected, and depending on your frame of reference the order in which the buttons are pressed can change. On the other hand, if you see those same buttons, one is pressed, then several seconds pass, and another is pressed, then they *are* causally connected, because light managed to cross the distance from one button to the other in the time between the presses. So now the order the buttons were pressed in is certain and independent from your frame of reference. This behaviour may seem weird, but it doesn't actually cause any problems or paradoxes. If you get into your spaceship and fly from point A to point B, your departure and your arrival are two causally connected events (because you travel at sub-light speed), and so have a definite order. But what happens if you make an FTL jump from A to B? Well, now your departure and your arrival are completely causally disconnected! And in certain frames of reference, arrival *occurs before departure*. Look what can happen now: - Make the jump A --> B - You are currently in the frame of reference where departure occured before arrival (as it should) - Engage your ship's thrusters and accelerate until you are in the frame of reference, where departure hasn't occured yet - Make the jump B --> A - You traveled back in time and broke causality! Crucial point is that breaking causality requires *two* FTL jumps in *different reference frames*. So, could there be some (purely hypothetical) mechanism that would allow FTL, but prevent paradoxes? Yes! There simply must exist a special frame of reference, and all FTL travel must only be possible in this special frame of reference. This special frame could be whatever, but for the purposes of this thought experiment we can pick the Co-Moving Frame (CMF), because it is easier to visualize and is already somewhat "special" (as mentioned in the video). Look what happens now: - Accelerate until your frame of reference matches CMF - Make the jump A --> B - Engage your ship's thrusters and accelerate until you are in the frame of reference, where departure hasn't occured yet (weird, but no paradoxes yet...) - Make the jump B --> A... but wait! You can't make this jump, since in the previous step you left the CMF! - Match the CMF again - Make the jump B --> A. - Since both jumps occured in the same frame of reference, causality is preserved! This is my understanding. You can search "fixed frame FTL" for some more info. see also this FAQ on Relativity which touches on this topic at the very end www.physicsguy.com/ftl/html/FTL_intro.html

[@petermoore900]

I don't think it has anything to do with GR TBH. Rather if you can guarantee that everyone can only move in such a way that everyone's arrow of time always moves in the same direction, then you can zip around faster than light - but still not infinitely fast! - without causing paradoxes. How can you guarantee that while lifting the c limit? Basically you'd have to hypothesize that there is something akin to subspace or hyperspace, that it indeed absolute, and that it is the only medium through which an FTL mechanism could work. Could this actually be true? Well it certainly can't be ruled out. Let's say we did make a warp drive. That would cause spacetime itself to bend and move. The stress energy tensor in GR is Lorentz invariant (meaning everyone agrees on the geometry of spacetime and thus the strength of gravity no matter how fast they're moving). Perhaps that means that all warp drives would indeed be riding waves in the same fixed and absolute medium and thus no paradoxes would be possible. But critically, again, this speed would still be limited - not by a single arbitrary number but by how fast an external observer is moving relative to "subspace". This limit is c^2/v where v is your velocity relative to the absolute frame. Specifically, instantaneous movement in any frame appears to an observer moving at v relative to that frame as c^2/v. So if we assume infinity is the speed limit of subspace, then on earth that speed would equate to roughly 1000c (if we're moving 300kps). Any faster perceived speed would indeed require the traveller to be going back in time in the frame of subspace. This means Voyager's trip home from the Delta Quadrant could've seemed instantaneous to the crew but 70 years would've passed on earth. In other words you can't fully escape time dilation but now it would depend on how fast the third party is moving relative to subspace rather than how fast the ship is going relative to the observer.

[@TomasSab3D]

Mass is compressed higghs field... If you can compress the higgs field "in front" of you, you will create mass to put behind of you, where it can expand back into higgs field. Push the condensate from in front - to behind you? or... push enough light together (no mass forward) to create unstable mass in front of you... and get pulled forward?

[@brianmucha6426]

Thanks Sabine for a very very enlightening video!❤

[@andrewrohde2373]

I watch Dr. Hossenfelder's videos in the same way that I read "A Brief History of Time." In the hope that I'll learn something, definitely not all, but something. And I usually do. Thanks Doc.

[@hailynewma9122]

Gonna watch this over and over again just to hear that I am not mass but pure energy … and today is not even my b-day .. thanks Sabine :)

[@wyqid]

I’d just like to say that I spend a lot of time watching KZbin and as a result I am becoming more massive.

[@user-bi2cb4hb7v]

Sabine, you've provided an awesome explanation! Superb!

[@moosewild4239]

This conversation is way above my pay grade but I find myself listening anyway. Your knowledge and ability to share it is appreciated. Subscribed since it is never too late to learn.

[@AverageSpaceJoe]

Your sense of humour is very refreshing...and drying at the same time...very confusing sensation 😊

[@MOSMASTERING]

My entire life, ever since I was very young, I always wanted or imagined a future version of myself to come back and just give me one or two pieces of advice that could alter or improve my life. I also thought what the smallest message could be. Instead of a book of instructions, just the fewest amount of words I would need. I'm now 42 and there are just two things I would tell myself with just 2 to 4 words that would entirely change my life and avoid so much pain and mistakes.

[@Tnker69]

Can't just say that without saying what you would say

[@Blindingsun]

“Don’t fuck Martha”. Or something along those lines?

[@tzerpa9446]

A train at 200 km/h. "If you live in the United States, make that 20" 😂 So funny, and so true.

[@stargazer7644]

We have trains in the US?

[@Thomas-gk42]

You have to work on it

[@jamiegagnon6390]

@@stargazer7644 I think they all crashed somewhere...

[@word6344]

rip any transport that isn't cars

[@jimbryce6982]

@@stargazer7644 Yes, but no Kilo Metres.

[@shelley-anneharrisberg7409]

One of the best yet! Really well explained, especially the Higgs Field Condensate and the time paradox! Guest appearance by Columbo with "Just one more thing" just really topped it off! (As did the socks in the washing machine - I like to think mine are in a state of superposition: they exist and don't exist at the same time. When I open the machine, their wave function collapses and I find they are there, or not - sorry Schrödinger, I just couldn't resist ;) ).

[@BlueGiant69202]

kzbin.info/www/bejne/e6TUhIyOZ9uVbdU

[@DalbyJoakim]

Yes this got somewhere very new! But there is no condensation for a scalar potential field! The condensation only happens when the field can form a sufficient density of sufficiently similar structures within that field: Higgs bosons or something even more simple, arranging themselves as a single entity of space-time. Or four space-times really, but three of them flow superluminally within ours - so I guess they are light invisible but gravity visible. Can information be harvested somehow about superluminal structures? Is there a before and after to us for superluminal structures, when they have an ortogonal time within them compared to the time within our structures?

[@antonystringfellow5152]

So that's how I end up with an odd number when I always buy them in pairs!

[@levybenathome]

Socks are explained by multiverse theory. Somewhere there is a universe with all of our socks.

[@GuinessOriginal]

I always find one is and one isn’t

[@seppopeuranen345]

Really love this channel and humor within. I seldom laugh out loud as I did with this

[@the_black_douglas9041]

True story about Anthrax weaponisation research: A young US Army infantryman called Bernard Vernon Kreh served in WW2 and participated in the Battle of the Bulge with the 69th Infantry Division. He speaks in memoirs about the horrors of liberating part of the Dachau complex. He was 18 at the time. The impression these experiences made made him unhesitatingly take up a job after his combat service as a worker in the infamous Fort Detrick. He worked on Anthrax and became accidentally infected. Bernard survived but a colleague did not. To this day, that strain of Anthrax is known by his initials, BVK-1. During the 1960s Bernard Kreh, better known as Lefty, became very famous as a writer and filmmaker about saltwtater fly fishing. One of the flies he invented features on US Postal stamp.

[@_mb_2617]

2 objections: 1) From about 9:00 onwards you say that the Higgs condesate was not present in early universe and the particles were massless, thus luminal. Then the simultanesous kick in of higgs effect and deceleration allowed particles to acquire mass while releasing finite amount of energy and slowing to become subluminal. But how does that prove that you can accelerate current massive particles to the speed of light (SoL) with finite energy. Obviously if you manipulate the mass of a particle, the energy it needs to acquire the speed of light is not given by the equation you show. That equation only applies to particles of constant rest mass. Which Higgs condensation violated in the early universe but which is true now. So you did not show that accelerating massive particles to SoL requires infinite energy, but only that at some point some particles decelareted from luminal speeds while simultaneously acquiring rest mass (in some rather specifing way). I still believe that while you can accelerate a these days electron very close to SoL, you cant get it exactly luminal. 2) At about 19:00 you speak about averaging over the whole universe and it seems to be one of the cornerstones in your overall argument, since based on it you disregard special relativity objections to some cases of superluminal travel. I can hardly belive you know how to do something like that properly. How do you actually compare local effects of distant stellar bodies in some point of spacetime? I believe that you can hardly support this argument, since this is pretty impossible to define reasonably and consistently in general curved spacetime. If you had something as FLRW universe on mind, sure you can do the described experiment far below the resolution on which the matter in the universe behaves as a perfect fluid and so I do not think that the argument applies. It seems to me you could in theory do the described experiment even very localy, like in a lab, and if you do not think Special Relativity would apply in that case, you are undermining one of the basic concepts of GR and making up a new theory. Please prove that your new theory describes everything better or equally to GR, until than i will stick with it. If anyone made it here note that I liked the interesting ideas in the video, I just had to rise the important objections so that the content is not automatically assumed to be true. I believe this is how sience should be done.

[@themysticalcolby]

Well said, thank you for your input.

[@jefferiestubeladd3261]

16:29 A timeline closed loop, got me to sit up straight and pay attention.😶

[@JustinTracey]

Thank you. This video made me have so many fun thoughts. I'm losing sleep, but in a good way.

[@staticgrass]

Very interesting and refreshing to see a take down on the “sacred timeline” argument against FTL travel.

[@fruitbatcat]

I don't know how u do it, but often during ur vods I find myself thinking I'm not sure I'm really following this or just think I am, then u drag me back in, you seem to know when those moments are and clarify the point. It's a real talent. Wish more lecturers had it. Just wanted to say :)

[@ignaciosavi7739]

She is probably full of shit and trying to sell books or something

[@ignaciosavi7739]

I was right

[@MIck-M]

She somehow 'brings me back in' with her quirky lil jokes which I like a lot. Mind like a steel trap and rapier wit this lady has.

[@jamesmeppler6375]

Just wanted to say smile face? LOL thats a lot of words for just :) I don't think you get it but at least you can understand you don't get it. Peoples intelligence can be measured by how others write or type. You can use commas but still using U for you and ur for your is either lazy or shows you're still very young. Understanding and being able to use real words is part of understanding what she's saying here. If you read 20 min a day for 10 years you will have a high IQ, maybe even genius level. Your reading comprehension will be maxed out so you'd know every word she said even if you don't get science. Umderstanding is the beginning of science. And if you understand the words the you can understand science

[@mattlambert3118]

You're not following her. You think you're not following because she says stuff that doesn't make any sense to you and then she "clarifies" by telling you the conclusion she draws from the stuff she said that didn't make any sense to you. That makes you feel like you're following because you understand the practical upshot of how she's saying things work, but you don't really understand why she she's saying things work that way. If you understood her reasoning for thinking things work that way, you'd understand that she's spouting nonsense.

[@jab-gn3sw]

Her humour is always good as her explanations are 😁

[@garytyme9384]

That, and she is completely wrong.

[@rekik2936]

@@garytyme9384 Enlighten us then🙄

[@garytyme9384]

@@rekik2936 Light does not have a speed, it has a rate of induction i.e., hysteresis of the medium. Take Red Shift as an example of Hysteresis of the medium.

[@neurotic3015]

@@garytyme9384 Dude, even if you believe that you can't just say she's wrong- Light having speed is so widely believed by people and scientists that you can't simply say everybody is incorrect without an extremely extremely good argument with paragraphs of wording and elaboration and good papers with variety to back the claims. We have far more reason to believe that light has speed than we do to believe it doesn't. For example- If light is simply inducted, than why do we get afterimages? Afterimages are produced because light from where something was and is hits your eyes at the same time, causing an effect of seeing an afterimage, but if we simply induct light, then we'd not see afterimages and instead we'd see everything perfectly as it moves.

[@garytyme9384]

​@@neurotic3015 Oh dear. I am chatting to a moron. Actually, you see the attribution of light i.e., illumination, and even then you are seeing the reflection of that illumination of the surface of the object you are looking at i.e., the illumination the object did no absorb. Hence, the after effect you are talking about is to do with the over stimulation of the eye. An afterimage is an image that continues to appear in the eyes after a period of exposure to the original image. These can be either negative or positive afterimages. In most cases, this is an eye-related phenomenon, although there are some cases in which it is related to an issue called palinopsia. Negative afterimages occur when the rods and cones, which are part of the retina, are overstimulated and become desensitized. This desensitization is strongest for cells viewing the brightest part of the image, but is weakest for those viewing the darkest. When you look away, the least depleted cells react strongest, and vice versa, and you see an image with colours that are the reverse of how the image originally appeared. Many optical illusions take advantage of negative afterimages. For example, if you stare at a yellow, green, and black American flag for 60 seconds, then look at a white background, you will see the flag with its correct colours. A positive afterimage is when you see the image, but it is the same colours as the original. Unlike with negative afterimages, it is believed positive afterimages are caused when your rods and cones have no stimulation, such as when the illumination abruptly go out. BTW: Answer me this Einstein - without breaking the law of conservation of energy. If illumination has a speed then explain how illumination returns to the same rate of "speed" after it exits glass or water? Bet you can't, lol,.. well not unless you factor in the hysteresis of the medium and illumination not being a particle, wave, or wave-particle duality. I say this as Nature does not work the way the mathematicians have tried to convince you of. I bet next you will say the quantum realm is a real thing and pigs can fly.

[@WaltC3]

Sabine is a marvel. Really enjoy her teaching style of injecting humor as an adjunct to understanding--what a difference it makes! I so much enjoy her open-ended, let's see what might be possible thinking instead of the same old negative reinforcement of so-called absolute limits--I agree with her--they only become absolute when we consider them to be absolute. I've always thought the "cosmic speed limit" definitions were lacking something indefinable, and she's actually helped me to understand why the barriers are not dead ends, but rather situations meant to be overcome. Great stuff. Now if only I could go back in time 50 years or so!...;) There always seems so much more to learn no matter how much you may think you know--you realize how much there is left to learn!

[@Verrisin]

"we are too boring for aliens to observe us" - Have you met people? - Some have hobbies studying the most boring of things. Others like to study ant colonies, or worms, or geology, knitting, watching how plants develop etc... - Surely, if there are many aliens, SOME would be interested in us, no matter how boring we might be.

[@eekee6034]

Yeah, the "too boring" hypothesis can't work.

[@tonywarren7940]

I would be very interested in a future video in which you say more about how mass is "created" by the condensed Higgs Field and the implications for how we think about the world

[@tylermacdonald8924]

Yeah this sounds kinda crazy

[@rainerzufall42]

Can you imagine a world only filled with plasma and energy? No protons, no neutrons, just quarks or even less "condensed" things? Because all the energy makes it so hot, that high level structures cease to exist? Think about it!

[@davisongeorge]

@@tylermacdonald8924 because it is, the binding energy of matter is actually negative, it was released when the matter was bound together into matter (at least for all non-transuranic stable matter) Now it's just negative potential energy. eg: it takes a huge amount of energy to unbind matter into it's constituent subatomic particles and even more energy to separate it into even smaller quantum particles like the higgs. That negative potential energy actually DECREASES the mass of matter, it doesn't create it, it's called the "mass defect". And honestly it seems like she switched the sign somewhere because if you plug that into the force equation, it takes more energy to accelerate to the speed of light, not less.

[@SaltyRad]

I appreciate your willingness to explore outside the box instead of just taking what is said as absolute truth

[@Babesinthewood97]

I’m gonna say something slightly unrelated and strange and I apologise in advance. But this reminds me of something I saw. 24 years ago I saw what I’d probably call a technologically advanced vehicle fly right over my head, completely silent, just above the roof tops and heading towards the sea. But, I couldn’t see the object itself but I only saw the light coming from it. It was super bright and it moved so fast that the light appeared like a wide “stripe “ of light in the sky just above me. About 20 meters wide. It took about two or three seconds to disappear from my view. Clearly it wasn’t the speed of light, but it was definitely faster than the speed of sound. I’ve always wondered what it was. It wasn’t a meteorite.

[@danielrutschman4618]

Maybe it was a beam of light. Light travels much faster than any aircraft, and is completely silent. It may have looked 20 meters wide to you, but you had no way of actually measuring it, did you? It could have been 2 millimeters wide but very close to you eye or it could have been 2000 kilometers wide but very far away, The one thing we know for sure is that it wasn't an alien spacecraft, because if it was they would have abducted you and you'd be famous now.

[@mind_of_a_darkhorse]

I love how you infuse humor into your explanations! It makes learning more enjoyable! Keep up the great work!

[@vickmackey24]

Do you actually laugh at her dry, corny jokes? Or do you just find them cute and endearing?

[@kszilvi86]

@@vickmackey24 Don't you happen to mix up "humor" with "laugh" tho? 2 verrrry different things...

[@mind_of_a_darkhorse]

@@vickmackey24 I find them endearing.

[@stevenbrown9185]

She is the absolute Queen of Deadpan

[@theprogram863]

@@vickmackey24 A little of both. Some are funny because they land, and some are funny because they _don't_ land. Her humor was much more hit-or-miss when the channel was new, but I'm really enjoying it now.

[@kamilstenzel3929]

Ok, Now I want a physics debate like that time Veritasium said electricity doesn't go through wires

[@cristiansandor4435]

The thing with the smashed eg is interesting. And indeed if a plane comes in your direction faster then sound, you hear nothing until the plane reaches you ( in 3D space ) and after that you can hear ( observe ) the sound created by the plane in reverse. The big BUT with this "travel back in time" is that events ( generated sounds ) it did happened in the past and you can only observe as they were ( still in past) and not able to "go back" and phisically interact with that event. The same happens with light, if faster than light, one can see events in reverse ( back in time ) but they are allready past events so only possible to see them ( and in reverse). So, with the Einstein theory even Tenet is not possible.

[@AnvilHammer-br1xp]

Thanks for the great discussion! I think part of this problem is that it's a parlour trick. Take Bob standing still and Alice goes by him at twice the speed of light.... " What does Bob SEE ? ". That's the problem... what do you mean, what can Bob see ? Is he still using light beams ? Light has a fixed speed limit... so... she's blown by him before the light recognizes him. So what does Bob see ???? a blur ? You cannot create a Bob and Alice situation and then use the premise that "What does Bob or Alice see... based on their speed... yada yada. That's why the time backwards thingy gets all messed up... you fell for the parlour trick :) To use this example you should not use "sight". Imagine there was a machine Bob could look in that could give him an image of Alice coming towards him at twice the speed of sound.... "What does Bob notice in the machine? The image of Alicia coming at him... then blowing by at twice the speed of light. no time travel.... The Parlour trick is they get you to focus on a faulty "sense"... IMHO.

[@citizensane1526]

You turned my brain into a black hole - the information that went in can’t ever be extracted from it 😵‍💫

[@tommycollier9172]

You have a physics teacher in middle school , I don't think we even had a science teacher in middle school

[@michaelwinter742]

I feel like she spends the whole video explaining that traveling back in time makes particles to be wave-like, a la what happens if you go back in time to send yourself a message. She reconstructed quantum physics from relativity. Go Sabine!!

[@dichebach]

You're crossed an important threshold in the quality and value of your presentations Professor Hossenfelder! A few more videos like this and I suspect your channel is going to explode . . . metaphorically speaking of course!

[@sf4137]

This is still a little too dry for the majority of humanity. Stepping stones.

[@dsmb9296]

@@sf4137 Maybe, but I bet a lot of those people would not be interested in the content anyway. Additionally, this "dry" method of presenting can be a good thing in itself and it seems her current subscribers really like it. She wouldn't be the only KZbinr to gain a huge subscriber count with minimal flair. Look at penguinz0. Besides, she has over 800k subscribers. That's pretty huge already.

[@rhondaeverett8284]

271,000 views on this so far!

[@andcheck]

@@rhondaeverett8284 I see 266,473 views right now. Am I moving backwards in time? Na, probably just the KZbin algorithm.

[@2ndfloorsongs]

@@andcheck I think you're right, the algorithm probably incorporates negative views, just like some physicists use negative energy.

[@welltell.]

I am just happy that some one was able to point out the obvious that you can not travel back in time by going forward at the speed of light.

[@PsychoticWolfie]

Makes about as much sense as Superman flying around the world backwards to turn back time. Physicists do have some brainfarts sometimes I guess.

[@klauskarpfen9039]

Watchers of Star Trek have known this all the time! After all, Captain Kirk and Spock would have encountered their future selves right at the beginning of each episodes and what a spoiler that would have been!

[@GlazeonthewickeR]

@@PsychoticWolfie Superman wasn’t written by physicists

[@Nazgul593]

@@PsychoticWolfie they just don't know ludicrous speed hyper speed is a lie. Jokes aside, darkness is in everything at once because it is always moving everything like a blackhole connected to all things at once, because of this everything infinite must also be changing and change is often harsh, while everything goes through cycles it is also changed and never exactly the same as prior, for this reason death exists and so does the void. Yes things can come back similar but never exactly the same, infinite thinking does not come without darkness and the void itself.

[@Nazgul593]

@@PsychoticWolfie Also Batman Destroyed Superman/God so stop using dumb watered down film depictions of modern trash media to try to make some sort of philosophical observation, it's insulting not just from people who understand more about this subject but also to video editors who don't just regurgitate basics and mundane ideas.

[@jadlevesque9363]

When I was little, I didn't like shrimps. I grew up, and now I do like them. I used to not like Sabine; I grew up since then. Thanks for the good videos

[@davidvomlehn4495]

I guess I slept in on the day where conservation of sox was presented. Not really a surprise, I slept in a lot. But the limit of the number of people who remember seeing Columbo is approaching zero far too fast. Edging closer to reality, salting the possible violation of causality with the flavor of Mach's Principle is new to me and much appreciated.

[@petermainwaringsx]

A quite unique way of presenting a scientific explanation. So much information mixed with some great humorous interludes. Thank you Sabine.

[@ilicdjo]

Very nice. I has a q; Is Bob Turkish Arab because of German collective guilt or of need for YT algorithm multicultural video?

[@DaCarnival]

@@ilicdjo Or because the average male on Earth is brown? Or because why default white to appease paranoid culture warriors like you?

[@reasonerenlightened2456]

There is no use for science if it can not solve the issue of distribution of Wealth and Power among the citizens.

[@kakistocracyusa]

No actual, competent, physicists would agree with you. If so many people actually think this channel's hand-waving, sophomoric and often false narratives qualify as an "explanation" , much less as competently presented hypotheses for creating new physics, then the human race is in trouble.

[@markovcd]

For years i'm interested in this topic and not once I've heard this argument.

[@Notivarg]

I think that the Aether and the Higgs-field might be more similar than you assume, especially in that first difference. Think about the question: why does light always travel with the same speed through a vacuum? Sure, c is its maximum velocity, but why can't it travel slower? Why can't it stop altogether like other particles? I think the answer lies in its wave nature more than its lack of mass. Waves need a medium to travel through and it's the medium that sets the wave's speed limit, and the Higgs-field might be that medium. A fish doesn't really experience water the same way we do. To us, the pressure at the bottom of the ocean is immense, but to the organisms that live there it's normal, neutral. Likewise, the air pressure at sea level is quite high in absolute terms (14 pounds per square inch is a LOT), yet we don't really feel it at all. So what's the pressure of vacuum? Not the pressure of particles in a vacuum, but of the vacuum itself? Gravity is described as curvature of space, but what is 'space' really? Imagine a black hole going at 10% the speed of light. At the center, the space distortion is supposed to be near-infinite. Within the schwarzschild radius nothing should be able to escape. Yet, the space behind the path of the black hole is restored to normal almost instantly - there are no 'space ruts' or long trails you can track the path of a black hole with. Is that not a sign of how high the pressure of space itself/the Higgs-field is? So what if the second difference isn't a difference either? What if the Higgs-field also moves, it just reaches a pressure equilibrium much faster than we can observe? What if the speed of light is the 'speed of sound' of the Higgs-field?

[@bandongogogo]

Dr Sabine's humor is so clever haha!!! boi you gotta love her!!! Keep it up!

[@lucadeeznuts7259]

Thank you very much Sabine for persevering hard times, taking the road less traveled, and making this happen every day. Don’t stop

[@HeadLikeARock]

"I'll even let you leave the toilet seat up". Not only have you got me thinking and educated me today, you also made me laugh out loud. Thanks Sabine! 😂👏

[@BlueGiant69202]

kzbin.info/www/bejne/rmTLaKuwappre7s

[@EarlWallaceNYC]

I loved this episode! But I don't (yet) understand it. This channel is a blessing to my life because: "It makes me to think". And, "thinking" is the joy of being human. Thanks.

[@nadamuchu]

agreed, I appreciate Sabine pushing us to the edge of our average Joe knowledge, but the second half of the video really lost me with some of the examples, especially the graphs of Alice and Bob. I'll rewatch it but not very hopeful I'll understand it more.

[@Felixr2]

@@nadamuchu Don't have a good resource readily available but if you want to get a better understanding of the graphs you can look up 'Minkowski diagrams', that's what those are called. I will tell you though that it's pretty much impossible to understand why all the lines move the way they do without understanding the mathematics behind special relativity, which is probably why Sabine didn't give a detailed explanation for that in the first place.

[@jonathonshanecrawford1840]

@@nadamuchu Is she thinking *outside the box?*

[@democratictotalitariansoci1462]

moral of the story is- while something can travel faster than light, it can't travel faster than time. If you send information at the speed of light to someone on a nearby planet, even if you get immediate response traveling faster than light, you'll receive that response in a future, no matter if it travels faster than light.

[@jonathonshanecrawford1840]

@@democratictotalitariansoci1462 Like emails, they may travel at the speed of light, but it may take minutes to receive due to connection speed, or even hours to respond, depending when one reads the emails, or replies in

[@jameshudson169]

I've been following this channel for 13 billion years.

[@cmvamerica9011]

There once was a lady from Frite Who’s speed was much faster than light She set out one day In a relative way And returned on the previous night

[@stephencummins7589]

I got to 8’ and said: I am so glad you made this new video, it makes everything so much easier to understand, thank you Sabine, I love your videos.

[@ukaszbartodziejski3662]

Sabine is the type of teacher who brings both knowledge and humor to the table - best mixture if u ask me in terms of learning experience :)

[@matbroomfield]

Dry humor at its finest.

[@havenbastion]

The humour bit is doubly impressive given thatEnglish isn't her first language and Germans are well known not to have any.

[@meangreencarpetcleaners3558]

I must've missed the humor 🤔

[@malcolmberke4862]

God has a sense of humor too. As we understand more of the physical universe, especially quantum physics, we also begin to understand the spiritual universe. This journey is however within ourselves. Our understanding that everything in the universe is conscious is a relatively recent development. As spiritual beings, we are made of energy. We can manipulate and control energy and matter. For example, without moving, think about raising your right hand. Now do it. It was your THOUGHT that made your hand move. You manipulated the physical with a thought! Likewise, the ability of remote viewing or astral travel can take you anywhere in the universe instantly. We are merely individual viewpoints of the universal consciousness. We are entangled with everything. Warp speed (faster than light) can occur because we think it. We simply must be practiced at moving scalar particles to manipulate the fabric of space to create a gravity well in front of the ship. Try this method the next time you go on a long drive. Spot a spot in front of the vehicle. Just pick a spot up ahead and then bring it in to your body. Repeat this process throughout the trip. This simple manipulation will reduce the amount of time to your destination (without speeding). We can not understand the physical universe until we first understand that we are the ones who create it.

[@matbroomfield]

@@malcolmberke4862 🤣

[@DarkwinggDuck]

For me the only way is to consider negative mass in GR like in Bondi extension of GR or like in bimetric gravity. Negative mass does not exist but it can be substituted by negative energy. Negative energy exists. Casimir effect has negative energy, two opposite charges also, two masses interacting gravitationally also. In Italy there is an ongoing experiment aimed at measuring the tiny repulsive gravitational effect of 2 Casimir plates. It is called 'Archimedes' experiement and it's done by INFN and CNR.

[@johnallen6945]

For the last 5 years or so, as a layman, I have been hypothesizing that the speed of thought may be faster than the speed of light at 186,000 miles per second. Thoughts don't have mass. I base this on the possibility that we may evolve telepathically at some point in the future. Also, "distant viewing," studies during the Cold War suggest that traveling long distances may be possible by mind travel alone without the body. You've given me some new lines of inquiry to research today so thank you for sharing.

[@enriquea.fonolla4495]

your "thoughts" are just sparking neurons interchanging electromagnetic information and those connections are NOT faster than light. I have no idea where you got the idea that we will become telepaths (thru science, yes, but naturally, no way). And astral projection and remote viewing are just BS.

[@washingtonradio]

I have always thought FTL limits were an artifact of our current theories. I'm reminded of George Box's comment, "All models are wrong, some are useful". To assume something is impossible because our current (incomplete and possibly incorrect) understanding says it is has always struck me as logical fallacy.

[@traumflug]

Fascinating. You not only manage to find cracks in currently popular physics arguments and can explain that with math, you also manage to explain this with graphics for non-physicists.

[@ItsEverythingElse]

Where is her math that explains how mass could even reach the speed of light, let alone exceed it?

[@traumflug]

@@ItsEverythingElse Please watch 5:52 closely again: _"the only way you can move at the speed of light is when your mass is zero"._ And then she explains why the stuff we know as matter might have states with no mass.

[@AlexBarbu]

Thanks for touching on the time travel paradoxes associated with faster than light travel. Can't say I understood it all, but at least I can understand that Special Relativity is not necessarily the be-all and end-all on this. I've seen this paradox being explained before (without the rebuttals you brought up) and I never could wrap my head around it. The way my limited, non physics Phd, mind sees it, no matter how fast the ship is going, it would still take positive time from Bob's perspective. I don't know how far Andromeda is, so I'll use the Sun in my example instead. I know light takes about 8 minutes to travel from the Sun to Earth. Let's say I can somehow reflect a laser I shine towards the Sun to bounce back to Earth. In this case, this laser light, from our perspective, would take 16 minutes to make the round trip. Replace the laser with a ship that travels at 2x the speed of light, and my limited brain's expectation is that it would take 8 minutes to make the round trip. 4x speed of light, only 4 minutes, and so on. As the ship nears infinite speed, the time would go towards 0, but it would never really reach it, just as it wouldn't reach infinite speed. So negative time, from Bob's perspective, makes even less sense to me. If anything, I expect the time dimension on the ship to be the one acting weird. From my understanding, light supposedly doesn't experience time, because of how fast it goes. So if something is moving faster than light, what then of time from that objects perspective? If below C you experience time, at C you don't experience time, why would something at above C experience time normally? Then there are some other weird points. If the ship is passing you by at greater than light speed, how would you even be able to give them the message? Any means you could envision of sending the message to the ship ultimately relies on the speed of light. Which means, since they're travelling faster than C, they simply wouldn't even be able to receive the message in the first place. They'd have to first slow down below C. In which case, you wouldn't even see the reverse of causality as it passes you by. It makes me think of Doppler shift, as an analogy. Just because the sounds of a car gets stretched out as it moves towards/away from us, doesn't mean that the engine's roar changes whether it moves towards/away from us. The whole thing is an illusion. To the point where by the time Bob sees the ship go by, the ship might have actually gone by anywhere between seconds to minutes ago. The worst part about how I heard this paradox being explained before, was the the guy was arguing that this proves even warp drives, or something like wormholes, are impossible. Which I found so odd, because the whole point of these FTL options is that the ship isn't actually traveling faster than light, it compresses space. Though, this makes me wonder, what would happen to a beam of light that passes by your ship, while the ship is folding space via a warp bubble? Would the light get blue shifted as a consequence of space compression?

[@ColbyAzimuth]

"Ein-SHtein." 🤗 I don't always speak the name out loud, but when I do speak the name, Sabine comes to mind, I smile, and say "SHH!" Shh! Just once though. Ein. SHHtein. It just makes me happy, I don't know why. My life will never be the same. Every conversation about EinSHHtein now has a little cartoon of Sabine popping up in the air right in front of me, saying it so distinctly.

[@philippschwartzerdt3431]

It’s great to listen to you and I love your dry sense of humor. I believe that I am learning a lot from your videos based on real knowledge. What’s even better, I am learning to question my position on many matters I took for granted without having to disappear in a rabbit hole. Thank you for making your community a little smarter with every video you post. 🙏🏻

[@jeechun]

"If you live in hte US..." hilarious. 😄

[@Axiomatic75]

Questioning one's beliefs is a rare trait

[@CARBON10]

You are the perfect person to subscribe to brilliant according to her

[@MindRebelion]

I love the way you carry a conversation and your demeanor, and your confidence is off the chart's admirable qualities of a scientist, thank you!

[@norfolknchance657]

why is the word "charts" possessive?

[@misterdutch2853]

There is finally hope that I can visit all the stars in this lifetime.

[@BuildTimeMC]

16:47 so, lets say a message is sent using a vehicle that can travel faster than light. As the message is transmitted, the event of its transmission creates a ‘time wave’ that propagates through time in all directions equally. Now, the Faster than light vehicle starts its return journey. As it travels back, it intersects with the ‘time wave’ created by its own departure. This intersection happens on the way back because the vehicle is moving faster than the speed of light, and thus, faster than the ‘time wave’ itself. However, due to the nature of this interaction, the vehicle doesn’t instantaneously arrive at its starting point. Instead, it arrives slightly after the moment it was initially sent. This delay represents the time it takes for the ‘time wave’ to propagate and for the vehicle to intersect with it.

[@Li.Siyuan]

One of your most thought-provoking episodes. Thank you, Sabine!

[@brianrajala7671]

Above my pay grade too. Either I was not born with enough of the right brain cells, or fed them the wrong foods, or else I slept through class the day these principles were discussed ... but I still find your lectures very interesting.

[@czhillimedia2391]

The message I just received from the Andromeda galaxy makes so much more sense now. Thanks Sabine!

[@andreweppink4498]

Dang. I'd think using Miguel Alcubierre's v>c Warp Factor 9 drive (somehow) would be a no brainer.

[@digilyd]

For a starter exercise for the brain, start with understanding all the issues that are caused be the speed of sound when recording combined video and sound recordings with multiple cameras and microphones.

[@Stone7C1]

just for anyone wondering. light inside a medium does technically not move slower than in a vacuum. its just a result of how were describing the process mathematically. whats really happening is, that light (photons) moving through a medium (at c) constantly collides with molecules and is absorbed by those molecules. there is a short delay (the average decay time of the excited state of the molecule) after which a new identical photon is emitted by the molecule that absorbed the previous one. this short delay is what were mathematically treating as light to moving "slower" through a medium, but not whats physically happening. in reality the photons are at all times moving at the same speed of light even inside a medium where they are repeatedly absorbed and simply stop existing entirely for brief moments. its like sometimes with electronic circuits you can either describe whats happening as negative charges flowing in one direction through a conductor, or you can pretend that positively charged particles are flowing into the opposite direction. mathematically it doesnt make a difference which of the cases you chose to describe whats happening, even though we know physically its electrons and not positively charged particles that are moving through the conductor. this is a good example to remember that the math were using is just a tool we use to describe physical processes and and can produce weird artefacts that do not accurately reflect what is physically happening in what we call reality but are still consistent within the mathematical model and still produce accurate results.

[@glomerol8300]

On the rare occasion when I read something more complex than usual that I wrote some time ago, sometimes I might not get what I was talking about, or at least not right away if I bother to try, so I can appreciate and empathize with that sort of case, Sabine. Great video... that I have a hard time understanding... But then again, I'm just a layperson WRT to the subject matter.