Can Axions Be Dark Matter?

We still don't know what is Dark Matter. We can see its effects but we don't know what it's made of. However, with their latest publication, Dr Amruth Alfred suggests that dark matter should be made of axions (which are one of the candidates among other particles).
Paper by Dr Amruth Alfred and his team:
www.nature.com/articles/s4155...
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00:00 Intro
02:19 WIMPs vs Axions
06:35 Observations
15:54 Implications for Cosmology
18:54 Where axioms come from
23:57 Difficulties with observations
27:54 How can the results be confirmed or debunked
31:13 Open-mindness in science
36:50 Gravitational lenses
54:35 Outro
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[@YousufAhmad0]

Fraser, seriously, you deserve to be awarded an honorary doctorate. I'm saying this as a scientist myself, and Dr Alfred just reinforced my point near the end of the interview. You posses and demonstrate all the traits expected of a PhD: breadth and depth of domain knowledge, an attention to detail, and creative ideation. I'm certain you would be prolific at authoring top quality research papers had you opted for a scientific career in academia or industry. But I'm thoroughly grateful that you chose journalism instead, because I genuinely believe you're doing a greater service to the community than any scientist singlehandedly could. Thank you

[@MrCoxmic]

I've had many "arguments" about this exact concept; sadly, the name string theory just rolls off the tongue better than string hypothesis.

[@prehistoricbody]

As a non-scientist, I concur 🎉

[@tonywells6990]

@@MrCoxmic Yes, a better name would be 'String quantum gravity'.

[@realkarfixer8208]

Yes! a scientist that is willing to correctly refer to String... as a "Hypotheses", as it hasn't been proven , yet to be a true "Theory" Thanks to Dr. Alfred and Fraser for a great interview!

[@seditt5146]

Yeah but he does this while talking about axions which have tons of evidence pointing towards them being nonexistent. String theory on the other hand covers traditional quantum physics relatively well and the only issue is that solidifying it would require particle detectors more powerful than we currently can make . We have had particle detectors which should create axions for decades yet here we are unable to find them despite considerable effort to do so. Particle physics has a serious serious issue right now with dark matter and axions leading those very issues and exemplifying them. Every other branch of science if you hypothesis does not match observation you toss the hypothesis and yet in particle physics if they don't match you change your model to a harder to detect form and ask for a few more million/billion because next time it will be there. Half a century we have been talking about these two things, darkmatter and axions yet neither really have a shred of evidence except for formulas which have been altered countless times for each after experiments have failed to produce results. Idk, I'll end my rant but this fellow has taken the two biggest problems in particle physics and merged it into one while shitting on a model that does rather well and towers above the model he is following.

[@tonywells6990]

'String Theory' is actually a theory, but not a scientific theory. It is a theoretical framework, but yes it is a poor name.

[@mikefeierberg7712]

You should have a regular series of videos with that guy to talk about what's going on in astrophysics. Of course, you are excellent on your own, but that was something special. I'm proud to be a patron and I'm glad you have enough patrons to keep your channel going.

[@CodyBrumfield1]

This was a great interview. All your guests are obviously doing amazing things but Dr. Alfred is an excellent communicator.

[@dropshot1967]

I find it amazing how you always manage to find these incredible people to interview. Thanks for yet another great podcast

[@realzachfluke1]

This was such an amazing interview, Fraser, thank you (and great questioning, for real!) I loved this guest, I really enjoyed hearing about his work and his mindset, and a big congratulations to the newly minted doctor for completing his PhD!!!

[@lucidmoses]

Finally you have a guest with good sound just to have bad lighting. :P

[@frasercain]

Hah, their lighting doesn't matter. Audio is everything.

[@lucidmoses]

@@frasercain Agreed. I mostly just listen to your guest ones. Just thought it was ironic. Bit funny.

[@zomboss-xb1st]

Could have been night for the guest 🤷‍♂️

[@amruthalfred]

Thanks so much for doing such an awesome interview with me Fraser, and a huge thanks to the viewers for their kind comments! Really happy to see that we managed to get the message across to people watching and not bore them to sleep - making Carl Sagan proud is my goal!

[@tinyderppotato5410]

Thank you for your time Dr🔭 hope to see you again on many channels!

[@sulljoh1]

I didn't know "halos" were spheres. Astronomers love their confusing terms. Fascinating interview & always nice to see more HK expats

[@christopherbrummet4997]

Nothing but love to your other guests who ran with Laptop or Tablet mics, but I 100% agree that having an excellent audio setup is a true pleasure to hear/see. This interview was really a pleasure to listen to!

[@alanmassoli5989]

What a great interview! Well done and thank you!

[@MCsCreations]

Fantastic interview, Fraser! Thanks a bunch! 😊 Stay safe there with your family! 🖖😊

[@AxelFougues]

I love it when there's a back and forth in the interview like a discussion rather than one way questions and answers

[@justin_5631]

I don't know about the science but I like what a clear speaker he is. It's orthogonal to the technical aspect but some people can be difficult to understand or follow.

[@dannybell926]

I really like this dude, thanks to both of you for the interview

[@AdamChristensen]

This was an AMAZING interview!!!

[@tbarsnessvfx]

gamer scientist! love it.

[@marvinmauldin4361]

I'm impressed that Dr. Alfred, early in his career, is willing to say that String Theory is a hypothesis and not a theory, since it is currently untestable and therefore unfalsifiable. Also, the referee who was more concerned with technical writing skills than content, was probably unqualified to judge the content. From his grasp of astrophysics, human nature, and office politics, Dr. Alfred should go far, as long as String Theory continues to redecline.

[@tonywells6990]

I doubt any physicist would confuse 'String theory' with a scientific theory. It is a theoretical framework just like any other.

[@charleslivingston2256]

I don't think he was critiquing the technical writing skills. I had the impression his issue was with saying there were problems that the WIMP models had difficulty handling.

[@Madash023]

This was a really fantastic interview. Thank you!

[@sadderwhiskeymann]

Very interesting interview! I am tempted to say amazing interview, but you interrupt the poor guy way too much (esp in the beginning) I'm glad he wasn't annoyed or loose his train of thought. (and yes, i've heard once explaining yourself about it as "to set the level of the discussion" but in this case it just doesn't apply) Nevertheless, good job Fraser!

[@jamesdubben3687]

Ok, I get it. the Audio was so great it actually sounded like you two were in the same room having a conversation. Dr. Amruth Alfred has a great attitude!

[@frasercain]

Exactly. I just bought a microphone for someone I'm going to be interviewing. I'm serious about fixing this.

[@circuitguy9750]

One of my favorite podcasts (Embedded FM) sends (low cost but good) Samson Meteor USB mics to all their guests. I know it's asking a lot, but it might be worth it for these high profile guests. Dr. Alfred really did raise the bar here. :)

[@RyanSandorRichards]

Sean Carrol does something similar to ensure the audio quality for his podcasts.

[@CosmicRadioOne]

Fraser: in terms of Dark Matter, what do you think about that fun and fascinating new theory being thrown about: how there may have been a "Dark Bang" in addition to our "Big Bang". Which in some interpretations would mean that 2 universes (each perhaps with varying laws of physics to each other) inflated into each other, and are occupying the same realm/space. Note: this is of course just a fringe hypothesis for now, but something fun to consider!

[@fiat_hater7761]

I read about this that we were thrust into an imploding part of the whole so to speak …

[@808bigisland]

That would explain incompatibility of certain measurements. We are a curved new universe expanding into an older static flat universe with a differing scale. There could be a superlarge interference pattern interweaved with the CMB and the various invisible 22 dimensions.

[@Chip_in]

Congratulations Dr Alfred and thanks Frazer brilliant interview is a great watch and listen ⛳

[@slo3337]

Interesting. I really like when new ideas come forth

[@prehistoricbody]

Fraiser just won major cred points 😂 so good as always.. waiting for the wormhole - dark matter double kill paper

[@jacobsoley4296]

Hi fraser. Are gravational waves affected by gravational lensing?

[@christycoffman]

This is wonderful!! Thank you again!

[@celestromel]

Brilliant sound! Brilliant guest!

[@DFSixe]

Is there a Blog or other site to follow Dr Amruth Alfred?

[@Corvaire]

I would imagine a "lens w/in a lens" would look like an odd directional smear in older data but with Webb an easy to find one would be a swirl at the edge of an arc (do to counter lensing.) Thanks for asking Fraser. ;O)-

[@pasteleiro98]

What now?.. I found this podcast just today, and i feel i am already addicted to it! I have to work, to be a mother, a daughter, i have to work for my community, i have my arts too... How am i going to manage this? Its 4am in the morning here @Lisbon, Portugal, and im still awaked watching and listening to you! Great job, Fraser! Awesome podcast! Than you! Both of you!

[@frasercain]

That is a tough one. I'd say, subscribe to the podcast and then listen while you're exercising, or doing art. But it is educational. :-)

[@triedproven9908]

Was a really good listen and it got me going. Two things. -Regarding gravitational lensing reconstructing and peering. Time dialation is a notion that hasn't been taken heavly into consideration. Dr. Alfred mentions these periods of brighting. It could be a conjoining of light from the same or different stellar objects from different time periods syncing up from our perspective giving us a picture that could be brighter or dimmer or altogether different from what occupied each galaxy during each time period. Two or more different sight lines in two or more different periods. It really makes reconstruction a shot in the dark unless both galaxies are periodically static relatively speaking. I hope that makes sense. - Axions and or Wimps... We assume the speed of light is the cosmic speed limit because from our observable perspective it is. However should we assume there are particles that travel at multiples of the speed of light; When they interact and either become constructive or destructive wave forms; this could result in the spots of cloud poofs Dr albert mentions for destructive wave forms and maybe something like worm holes for constructive wave forms. Summarizing: A destructive clashing of particles traveling in excess of our observable limit would make them observable to us as the release of energy would slow the particles resulting in a release of photons and higgs particles as they enter into our plane of existence. Conjoining faster than light particles which already have a indeterminable warp factor would multiply their speed and thus warp factor. There would also be an associated spin. Which is what I believe would produce a worm hole as the interaction would further warp time space or completely pull time space apart, open or through with enough in phase interactions. I've never ascribed to the notion of wimps simply because with what we currently know the more mass particles have the more they will invariably interact. But an axion moving so fast having so much energy it's unable to release that energy to particles which simply cannot interact with it's valence field just makes sense. They are self contained particles because they exist in a warp field factor which only other particles at that factor or higher can interact with.

[@tonywells6990]

Time dilation doesn't effect any observations like that. Fast moving particles can cause boosting of light in quasar jets. I don't know if you mean differing time paths which is really interesting in multiple images in gravitational lenses. One image of the galaxy could be delayed by a few years compared to another which has been observed before.

[@triedproven9908]

@@tonywells6990 Yes. Differing time paths overlaying in the lensing view from the perspective of the observer. It's not a thing yet. But I'd think it to be completely plausible. It'd take some time and considerable amount of accurate observation to be proven however.

[@nakedsnak]

Great interview thanks!

[@frasercain]

I'm really glad you enjoyed it.

[@ricardoabh3242]

This was fun, would have like to see some what-if images/curves of this potential radio images that would separate these hypotheses

[@NinoT111a]

thank U Fraser for keeping the interviews within limits understandable to us mortals. respect

[@frasercain]

I'm glad you're enjoying them.

[@meskahmusic]

Amazing ones!

[@richardmarkham8369]

Great video. Mind bending!

[@lurkst3r]

did a rudimentary search and cant find the doc, would love to follow on twitter.

[@ToxisLT]

loved it! thanks

[@DanBennett]

I love your show!

[@SomeoneExchangeable]

@Dr. Alfred: That most of the critique was on the introduction instead of the "meat" of the paper sounds like you had a "bicycle shed problem". That is when people will try to make as many comments as they could about the only thing they understood, because they can't admit that they didn't understand any of the rest.

[@richardloewen7177]

Absolutely wonderful, having guests that exhibit critical openness, which you can discuss at a thinking about thinking (metacognitive) level. Re this topic. I was greatly helped, in my own thinking, by an astronomer who did a metacognitive analysis. He said: 1) Orbital anomalies can come from either overlooked mass or overlooked physics. 2) Astronomers have a predeliction towards previously overlooked mass. His examples: A demonstration of previously overlooked mass involves orbital anomalies of Uranus. A farther out big planet was predicted. A high-probability location was predicted. In it, Neptune was found. It works! Later, spotted were orbital anomalies of Mercury. By the same line of reasoning, a planet Vulcan, closer to the sun than Mercury, was first sought. BUT Einstein's General Relativity--previously overlooked physics--sufficiently explained the anomalies. AND, no Vulcan was found. The same predeliction, to look first for previously overlooked mass, is also present in the present case of seeing orbital anomalies in a distant galaxy. We are far away. We cannot directly inspect the situation. We have to guess. Thus, the obsessive focus on dark matter, done WITHOUT conclusively eliminating the other possible explanation.

[@tonywells6990]

90 years of trying to eliminate all other possible matter (such as black holes, primordial black holes and neutral gas) has led to the conclusion that dark matter is still there shaping the structure of the universe. Almost all of the predicted baryonic matter has been found.

[@ioresult]

I think you made an impression! "Are you an astronomer?" and "You play too!?" haha!

[@Mr_Kyle_]

QUESTION 8:00 What if some form of MOND is correct and gravity behaves differently on large scales - wouldn't that affect gravitational lensing and potentially distort light/distance/spectroscopy of the being viewed in this way?

[@montyzx7r]

This is the best interview by far, this bloke it truly smart !!!!! ... credit to both of u for ur work....cheers mate for your channel

[@triskeliand]

Axion is a detergent that makes bubbles? Or Froth?

[@amarq1509]

Thoughts on... "The novel new approach is detailed in a paper published June 2 in the journal Classical and Quantum Gravity, by University of Geneva professor of theoretical physics Lucas Lombriser."

[@arlisnarusberk]

thank you

[@KaliferDeil]

Could Axions be responsible for radioactive decay? If they are almost everywhere and radioactive decay is probabilistic, it seems possible that one could affect or even be causal for the other.

[@tonywells6990]

No. Decay is already modelled by quantum mechanics (QCD/QED) which does not include Axions (not yet at least).

[@peterclarke3020]

These ‘very light’, long wavelength ‘particles’ sound interesting. What kind or order of wavelength do you think they might be ? (if they actually existed) For example are we hypothesising something like 1 km wavelength ?

[@tonywells6990]

The wavelengths discussed here are on the order of light years, or 9 trillion km, which would explain the large scale of superfluidity of dark matter within and around galaxies. The mass of these ultra light dark matter Axions is something like 10^-22 eV/c^2. The problem is some experiments have already hinted that this sort of mass range should be ruled out. Standard model Axions are more in the range of 10^-5 to 10^-3 eV/c^2. Which would have a wavelength of centimetres or metres.

[@DrDeuteron]

So very long wave length optics would produce major variations in the observed brightness of a lensed source, that is 200+ year old optics. But why would the waves be coherent?

[@robotaholic]

You're the best!

[@nerufer]

dota 2 is awesome. now i want to play it again too fraser

[@jacobmygindpedersen1138]

That was great. What a nice and smart guy.

[@Becidgreat]

Can you test outside space/time? I don’t think dark matter is only present in space time

[@lgme378]

So ... still no idea yet, just hypotheses at best if the Axion is backed by "String Theory". And A. Einstein got a Nobel price for something fundamental in partical physics. Yes he should have had one or two for SR and GR.

[@frasercain]

Nope, but that's how it works. You make an observation, try to come up with some theories that could explain it, and then try to collect data to try and disprove your hypothesis. Rinse repeat.

[@ashleyobrien4937]

I was thinking, if Fraser keeps all the hair from his beard trimming, he could smear his head with superglue and then sprinkle them on top, to give him that "youthful virile don't F with me look"......

[@user-ln5nk7mg4v]

Video didn't describe clearly enough to me what an axiom is, still a 'dark' idea to me. That is, are all axioms waves and what part of the spectrum is this 'type of axiom' compared to other 'types of axiom'?

[@Cheezeakamp]

I explained it below

[@mario-ck3es]

Someone explain to me I'm missing what his team found that could potentially dis prove dark matter

[@KenMathis1]

They found that their model for dark matter using the light axions more accurately reproduces the results of gravitational lensing than models using heavier particles. The key difference between the two is that a heavier particle behaves more like point objects while lighter particles behave more like waves. It's that wave pattern in the images that they say best describes the lensing results. From their paper... Key: ϱDM = heavy particle dark matter ψDM = light wave like dark matter "Whereas ϱDM lens models leave well documented anomalies between the predicted and observed brightnesses and positions of multiply lensed images, ψDM lens models correctly predict the level of anomalies remaining with ϱDM lens models. More challengingly, when subjected to a battery of tests for reproducing the quadruply lensed triplet images in the system HS 0810+2554, ψDM is able to reproduce all aspects of this system whereas ϱDM often fails."

[@tonywells6990]

This is a potential observation of dark matter, but whether it's an Axion is another question.

[@triskeliand]

Can mass perpetually decrease until it reaches an escape velocity with respect to gravity interactions....? i.e. Dark matter? Some bit of dust that is "collapsing its mass" faster than the universes ability to see it? Getting smaller and smaller, lighter and lighter, Faster and faster, but still interfering with the fabric of the universes gravity as it continues to cease to exist.

[@Dlweta57]

Interesting theory, but I can't reconcile as your theory conflicts with the laws of entropy , maybe unknown physics mite have an area that supports your idea

[@rkreike]

Q: When objects or debris around the centre of a whirlpool in water are attracted to that centre, then is that attraction because of dark matter?

[@hipser]

Wow. this was illuminating af. Thanks to both of you's!

[@sulljoh1]

No twitch link? 🤣

[@seditt5146]

Forgive me if its cleared up as I am just starting the video but he stated DM has had tons of time and money looking for it with no success however all that pales in comparison to the time and money spent looking for Axions. Axions have changed their form multiple times as some physicist are unable to accept they simply are unlikely to exist. Its kinda bad form to look for the one particle we cant detect by using another particle we have not been able to detect unless your goal is to milk the physics money machine because if that is your goal mixing Axions with DM is your gold mine without a doubt as millions are tossed in and the search is unlikely to ever ever end.

[@frasercain]

You're saying that more money has been spent searching for axions than other forms of dark matter? Is there a study or some kind of document that talks about this?

[@seditt5146]

@@frasercain is the reply i just sent visible or perhaps in a waiting room due to the link I sent or is it for some reason lost to YT because I personally don't see the reply I just sent.

[@frasercain]

KZbin will automatically block links because that's how spammers operate. I'll see if I can find it.

[@seditt5146]

@@frasercain I suspected as much Ty. It's not a huge deal since I am talking to you personally you can see it in your held for review area. It honestly was just a link to one of the first hits on the non detection of axions. From now on I'll just post DOI numbers and what not when it comes to academic papers.

[@frasercain]

I was more interested in your claim about the total budget being spent. The discussion about the nature of dark matter is lively with papers debunking other papers. But you said the budget for dark matter "pales in comparison" to the budget spent on axions.

[@triskeliand]

Technically I failed at two pHDs, one was on Modelling RNA evolution on Sunsystem supercomputers in the 90s at Massey university under Prof. David Penny and the 2nd one was Liquid Crystalline DNA evolution in Dinoflagellates at HKUST in Hong Kong under Dr Joseph Wong. I couldn't face the reductionism I think.

[@alexdevey3188]

Has it anything to do with the fact we are observing it. ?

[@THIS---GUY]

You should listen to Roger Penrose and Jordan Peterson. He answers this question specifically

[@Cheezeakamp]

I think u can have 5 phdS n 90degrees but still not see thats just liturally amount into cubed minds but have 0 pointed values. Warm n hot is only felt by those who can freeze or burn. Whats temprature without a human seeing it as cold brrrr or hot ahhhhhhtttt...im not going further 0 point... hope i kinda hinted nothing...

[@j7ndominica051]

I tend not to watch streaming videos where they put up two heads because of the atrocious quality. He could use whatever microphone, but record the video locally and skip the web-crap streaming.

[@frasercain]

That's why I stopped streaming my interviews. The quality suffered.

[@PixelOverload]

I think it's 'cause "spherical cloud" has _always_ been the definition of "halo", the ring over the head is a very modern idea. You don't see many depictions of angels with head rings until the last century or so, in older works they near universally appear within a sphere of light, _that's_ a halo. Not sure where/when the head rings originate tho, my guess would be theatre 🤷

[@DFSixe]

I hope I live long enough to see this young man receive his Noble Award in Astronomy for disproving Dark Matters Existence.

[@frasercain]

He thinks it's made of axions, so he definitely thinks it exists.

[@michaelkahn8744]

We've spent almost a century to find Dark Matter and Dark Energy but still there's no sign of them. No matter what we try, a thing which doesn't exist can't be found. May be it is time to find an Alternative Way to Explain Dark Matter and Dark Energy. 4-D Hypershere model of Universe can easily explain Dark Matter, Dark Energy, Void and even the reason why the measurement values of Expansion Rate are around 70 km/sec-Mpc. Dark Matter, Dark Energy, Gravity, Void and Antigravity, ... all these are same phenomena. They just look different. I agree to the idea that the interaction between mass and space must be explained with quantum mechanics. But that doesn't mean gravity is the QM phenomena. That's because gravity is not a force. Dark Matter, Dark Energy, Gravity, Antigravity, Void... all these are just joint effects of the expansion of the Universe and the curvature of spacetime. Details are given below. Einstein’s theory of General Relativity states that spacetime is curved by the presence of mass. This curvature influences the motion other objects with mass and gives rise to gravitation. Thus, gravity is a result of geometric features in spacetime. However, we also observe gravitational effects - curvature of spacetime - in areas without any detectable mass. This has given rise to the concept of dark matter, which is matter that does not interact in any detectable way with normal matter, except through gravity. So, there is some large quantity of dark matter scattered throughout the universe, which curves spacetime and causes gravitational effects just like normal matter, but we cannot see or detect it with any known method. An alternative theory to the identity of dark matter is proposed - it is not matter at all, but rather an intrinsic curvature of spacetime. In other words, spacetime is not naturally flat. Even in the absence of matter, we observe some inherent curvature of spacetime. So, the question is now - why is spacetime naturally curved? Why is it not flat in the absence of mass? The universe is 4-dimensional, with 3 spatial dimensions and one dimension in time. Rather than consider time as a linear dimension, we can consider it as a radial one. Therefore, rather than describing the universe with a Cartesian coordinate system, we describe it with a 4-dimensional spherical coordinate system - 3 angular coordinates, φ1, φ2, φ3, and one radial coordinate in time, t. We live on the 3-dimensional surface of a 4-dimensional bubble which is expanding radially in time. Thus, the Big Bang represents t=0, the beginning of time. The crucial point is that the expansion of the universe is not homogeneous in all directions. The expansion rate at one point on the bubble’s surface may differ slightly from another point near it. The universe is only roughly spherical in 4 dimensions, the same way that the Earth is only roughly spherical in 3 dimensions. The same way we observe local mountains and valleys on the surface of Earth, we observe local “mountains” and “valleys” on the surface of the universe bubble. The inhomogeneity of the expansion of the universe has given rise to natural curvature of spacetime. This natural curvature causes the phenomenon of “dark matter”. “Valleys” in spacetime pull matter in, similarly to the warping of spacetime of massive objects. So “dark matter” is really “valleys” in spacetime that are expanding slower than the regions surrounding it. These valleys tend to pull matter in and create planets, stars, and galaxies - regions of space with higher-than-average densities of mass. Conversely, “mountains” in spacetime will repel matter away, an “anti-gravitational” effect, which gives rise to cosmic voids in space where we observe no matter. Each point on the surface of the universe bubble traces out a time arrow in 4-dimensional space, perpendicular to the surface. These time arrows are not parallel to each other since the universe is not flat. This causes points to have nonzero relative velocity away from each other. It is generally accepted that the universe is expanding faster than observable energy can explain, and this is expansion is believe to be still accelerating. The “missing” energy required to explain these observations has given rise to the theory of dark energy. The time dilation caused by non-parallel time arrows can be proposed as an explanation for dark energy. Alternatively, dark energy is real energy coming from potential energy gradients caused by non-parallel time arrows. As a sanity check, we can calculate the expansion rate of the universe based on the universe bubble model. Since the radius of the universe bubble is expanding at the speed of light in the time direction, it increases at 1 light second per second. Therefore, the “circumference” of the 3-dimensional surface increases by 2π light seconds per second, or about 1.88*10^6 km/s. This expansion is distributed equally across the 3-dimensional surface, so the actual observed expansion rate is proportional to the distance from the observer. At present, the age of the universe is estimated to be 13.8 billion years, so the radius of the universe bubble is 13.8 billion light years, or about 4233 megaparsecs (3.26 million light years to 1 Mpc). Thus, we can calculate the expansion rate of the universe, per megaparsec from the observer, as: Expansion rate = ((d(circumference))/dt)/radiusofuniverse=(1.88*〖10〗^6 km⁄s)/(2π*4233Mpc)=(1.88*〖10〗^6 km⁄s)/26598Mpc=70.82(km⁄s)/Mpc The popularly accepted empirical expansion rate is 73.5 +/- 2.5 km/s/Mpc, so our calculated value is close. There may be some additional source of expansion (or observed red shift) to make up for the discrepancy. For example, if two adjacent points have some gravitational gradient due to non-parallel time arrows, then light passing through these points will be red-shifted. - Cited from www.academia.edu/82481487/Title_Alternative_Explanation_of_Dark_Matter_and_Dark_Energy

[@marcomattano3705]

Apparently, there's no dark matter - and no dark energy for what it matters - and even the expansion of the universe is a mirage as particle masses evolve over time as it's field fluctuates, thus creating the redshift effect (and cosmological constant) we observe on distant galaxies.

[@beachboardfan9544]

How does Dr Alfred not have a yt channel!? WTF get on it! Feel like it should b mandatory for all PHD's to have yt channels nowadays...

[@JungleJargon]

Dark matter isn’t needed. GR alone explains everything we see. *Solution to the "Time Light Problem"* The reason why people often stumble over the *assumption* that light years in outer space equals the same measure of distance and passage of time on earth is because general relativity is not being taken into account. In general relativity, the local rate of time and the measure of distance depend on the amount of matter or mass in the vicinity. Locally, the rate of time and measure of distance doesn't change much inside of our galaxy. However, the distance in our line of sight between us and distant galaxies is extreme and running at a much faster rate of time as well as an expanded measure of distance outside our galaxy compared to where we are near Sagittarius A's Milky Way black hole (where our rate of time is much slower and our measure of distance is much more contracted). The same way the earth appears flat locally, our universe also appears to be flat locally. However, over great distances throughout the universe there are differing measures of distance and differing rates of time. From black holes to the lagrange points between black holes there is very little acceleration compared to our relatively flat contracted local frames of reference near Sagittarius A. When we observe other galaxies, we are effectively looking at vastly differing measures of time and distance relative to our local observations within the gravitational force of the mass of the Milky Way galaxy. This can lead to various observed phenomena as we look into outer space such as redshift, superluminal motion and the apparent faster motion of the outer spiral arms of galaxies. It's not the same as our flat observations of cats and dogs locally here on earth where we don't observe differing measures of distance and time. So the supposed expansion of the universe, imaginary inflatons, invisible dark matter and dark energy or vacuum energy are *not* required to explain the observed redshift of light from distant galaxies or the faster than expected motion of the outer spiral arms of galaxies. As predicted by general relativity, the expanded space between galaxies due to the absence of matter in our line of sight where much less acceleration can explain the observed redshift without the need for a nonsensical universe expanding into oblivion for no apparent reason and it explains the faster than expected motion of structures and objects the farther it is from supermassive black holes. It turns out that the vacuum energy of space is due to the frame dragging of black holes that are growing from gobbling up spacetime regardless of the amount of matter being consumed. Recent findings of a team of scientists have found that dark energy or vacuum energy is associated with supermassive black holes that are all growing in size, as opposed to an ever expanding universe. It turns out that light is blue shifted going into a gravitational well so the converse is true of being redshifted traveling great distances outside of gravitational wells. Supermassive black holes are the most powerful forces in the universe with far reaching effects of gravity and vacuum energy. The problem and solution is that between galaxies, all of the galaxies all around are all together pulling and drawing in spacetime as well as exerting equal gravitational forces on empty space. This is the reason there is very little acceleration between galaxies and where there is expanded distance and a faster rate of time. The clocks are running faster outside of galaxies and the measuring sticks are larger meaning things are actually less distant than they appear. The more gravity drops off outside of the galaxy and in between galaxies, the more distance will be expanded and the faster the rate of time will be. As predicted by general relativity, the expanded space between galaxies due to the absence of matter in our line of sight where there is less acceleration explains the observed redshift without the need for a nonsensical universe expanding into oblivion for no apparent reason at all. The differing rates of time and differing measures of distance also explain *how* a day is the same as a thousand years and a thousand years is the same as a day, at the same time in the same universe. 13.8 billion years is the same as 6,000 years and 6,000 years is the same as 13.8 billion years *within the same created universe!*

[@hive_indicator318]

Fraser, why do they call it dark matter? Isn't the main (if not only) thing that is known for sure is that there is unexplained gravity? Sure, the only other way we've detected gravity is through matter, but isn't that still an assumption here? Why frame the question in such a way as to suppose a type of matter when calling it Mystery Gravity fits what we actually know?

[@frasercain]

It's a terrible name. It's just a catch-all for a series of observations by astronomers. It might not be matter at all

[@Cheezeakamp]

I do

[@tk423b]

Maybe just maybe magnetic fields have more to do with galactic motion than is being considered.

[@PhysicsPolice]

33:33 This is a misrepresentation of history. Relativity was quickly accepted by the theoretical community in 1910 and gained near universal acceptance when it was confirmed experimentally in 1919. This all happened before he was awarded the deferred 1921 Nobel prize. The committee didn't choose the photoelectric effect due to any lack of acceptance of relativity. It was in their eyes a discovery of more practical importance. I don't necessarily agree. Doesn't change history.

[@tonywells6990]

There is a big difference between special relativity (1905) and general relativity (1915). He did however win his Nobel "for his services to Theoretical Physics, and especially for his discovery of the law of the photoelectric effect".

[@PhysicsPolice]

@@tonywells6990 Yeah. That quote shows they appreciated all his work, presumably including SR and GR. They had to select one discovery in particular because that’s how the prize works.

[@ronigbzjr]

Another amazing interview. I'm loving how people with PhDs get amazed by Fraser's knowledge lol 😂😊

[@DrDeuteron]

but how do light particles get cold?

[@tonywells6990]

Not sure which model his Axion's are based on but some models predict that Axions were produced just after the big bang and they lost most of their energy (mass and kinetic energy) to other particle fields, which means they started to move very slowly and became very low mass. 'Cold' particles can also describe massive particles that move slowly (WIMP's of cold dark matter). An example of 'hot' matter are neutrinos which are light and move very close to the speed of light. There are also thought to be cold neutrinos that were created just after the big bang but have slowed down over time due to the expansion of the universe. Other particles, such as electrons and atoms, can be slowed down in magnetic fields or by lasers for example and become 'cold'.

[@FrancisFjordCupola]

I wouldn't call the question of what dark matter is an age-old question. It's hardly been even a century of having indications it is out there. With only in the last few decades serious developments into everything needed for investigations and observations. I don't think axions (let alone string theory) is useful as a solution because both of those have been more nebulous than dark matter. One could easily posit that strings are made up of movinggoalpostium. Intuitively, though, the less interactive a particle would be, the more its wave counterpart should come to the fore.

[@DanBennett]

And now behold: The Axions!

[@Cheezeakamp]

Ok so did u figure it out finally?

[@krumplethemal8831]

Dark Matter is just gravitational lag. Gravity is limited to the speed of light. Large masses can generate gravitational fields that stretch for tens of thousands of light years. All objects within the galaxy are moving. Imagine an invisible boat on a lake. You can tell there is a boat if it is moving because it will disturb the water leaving troughs behind it. You can even calculate the velocity of the boat by measuring the trough. You can even tell the direction the boat is heading, even though the boat is invisible. As large stellar black holes orbit the galaxy they leave behind them a trough of a gravitational field that lags behind it as the black hole moves faster than the trough dissipates behind its tangent. This means objects that pass into this gravitational trough are influenced by the gravity field even though there is NO OBJECT there. This is why we can't detect anything causing dark matter. (particle physics) Why we assume it interacts with everything except itself. Why we can't locate it locally. Still explains gravitational lensing. Still explains rotational velocity of the galaxy. Still explains why it seems to make up a large portion of the universe.

[@hibris9723]

I really liked and felt satisfied with this explanation. Thanks

[@pauldhoff]

What is Dark Matter made of, Dark Matter, Geeezzzzzzzzzzzz. Next question.

[@doncarlodivargas5497]

And atoms are made of atoms and photons are made of photons, just a few more minutes now we have solved most questions, a Nobel prize is waiting

[@imakedookie]

I want to watch that nomination live!

[@yewtoob2007]

Frasier Dota2 Twitch stream coming this summer!

[@FloridaMan69.]

maybe it's negative gravity

[@josephgardner5891]

BEC + the now known G wave orchestra = dark matter +_ or doesn't really which, if right the universe is saved.

[@paintballercali]

I'm sure it's a lot of different things

[@HeyHeyHarmonicaLuke]

54:40 "I'm on Twitter" "I'm sorry." Is it that bad on Twitter :O

[@frasercain]

It's been better.

[@doncarlodivargas5497]

How can something both influence on matter with its gravity and at the same time not be part of stars and planets? If there is 6 times more dark matter than "our" matter, how come i do not weigh 600kg?

[@JenksAnro]

Well Dark Matter doesn't seem to be present on earth, but it is observable in the behaviour of galaxies. But I'm a modified gravity believer more than a dark matter believer

[@doncarlodivargas5497]

@@JenksAnro - exactly, this is what I ask, how come I attract meteors, but not dark matter if it is both connected to me via gravity?

[@michaelpettersson4919]

Because you contain very little dark matter yourself. This make the stuff even more odd since there are whole galaxies out there with very little dark matter in them. This means that the stuff isn't evenly spread.

[@doncarlodivargas5497]

@@michaelpettersson4919 - are we not told galaxies are kept together exactly because of dark matter!? And my point here is there should be much more dark matter than ordinary matter, so even if there is less, even if there is only fraction of the amount elsewhere, I should weigh 200 or 300 kg?

[@michaelpettersson4919]

@@doncarlodivargas5497 Our typical galaxies yes. There are some atypical ones as well and they probably got dark matter as well but considerably less then what is typically expected.

[@robertmartin2262]

Did anyone else notice his ketamine drip, he was trying to wipe it halfway through, then I noticed the white in his mustache, oh dear, on Fraser Cain, how appropriate.

[@frasercain]

That would explain my enthusiasm for this topic.

[@BenjaminSteber]

I have an alternative theory for dark matter, and I submit that every mathematical and observational tool needed to understand the 'dark matter' phenomenon not only exists now, but has existed for decades.

[@fiat_hater7761]

I’ll prob get a lot of flack from the dark matter people - but it’s only cool people listening … great guest!

[@bigianh]

Could have been worse could have been Mr Muscle ;)

[@deltalima6703]

Fraser wasnt lying. Thats the answer you give if you really do play. "No effing way, I fully understand you will wipe the board with me, its about as 'lucky' as chess! I will just look dumb! :D"

[@frasercain]

I'm not going to feed him.

[@deltalima6703]

😃👍

[@ArmyGuyClaude]

I guess it's made out of matter.... that's dark.

[@imakedookie]

Wow you've solved it then! We can harness that and put forth a new evolution of humanity! Yay!

[@ArmyGuyClaude]

@@imakedookie Thank you thank you no applause just money.

[@imakedookie]

@@ArmyGuyClaude 0.01 has been deposited in your account sir!

[@freehat2722]

OMG I've been talking about interference for a while now. For sure neutrinos and black holes should be considered as dark matter. I think there are other forces at work (e.g. electromagnetism). After considering all of the forces and interference patterns it should open up new views on cosmology.

[@frasercain]

It's a really fascinating result.