why is it always rubidium?

[@megapussi]

"why is it always rubidium?" me who has never thought about rubidium a single time in my entire life: "honestly yeah why is it always rubidium?"

[@zombieregime]

Periodic table description: rubidium has little use Everyone using rubidium based atomic clocks for precision oscillator discipline: ... 🥺...

[@gasdive]

I thought about it when the Bose Einstein condensate hit the news, and not once since. But my experience was the same.

[@RedKincaid]

I clicked on this video entirely because it was a question that I had never heard before in my life and it somehow jarred me out of my endless scrolling with curiosity

[@garyha2650]

Why Rubidium for me became what is sleeping under her books

[@kevinnivek8907]

@@garyha2650she should give it a name….ANY ideas? 😅

[@gcewing]

Indiana Jones and the Spectrogram of Doom: "Rubidium! Why does it always have to be rubidium?"

[@burgerforcongress1001]

My first thought was of Shrek, "Why is it always midnight?" Midnight is actually kinda annoying to use as a deadline, because it's 12:00 AM, which actually belongs to the day it STARTS. Not everybody actually knows that, so it's easy for somebody to think they have a day more than they actually do before the deadline. Now, if you say it's 11:59 PM on *date*, nobody is getting confused.

[@richardfarrer5616]

@@burgerforcongress1001 In the UK army (or at least in the military hospital my mother worked in at one point), midnight was considered a free minute for exactly that reason. Orders always stopped at 23:59 and started at 00:01.

[@michaelcoletta4547]

IT'S MAGIC Y'ALL

[@suttoncoldfield9318]

@@burgerforcongress1001 I assert that surely midnight is 00:00

[@danatronics9039]

@@suttoncoldfield9318 Preposterous. It's clearly 24:00

[@nujuat]

AMO physicist who has worked with rubidium BECs here. Theres one more useful thing about rubidium that makes it nice to use. You mentioned that rubidium is cooled using lasers, but what lasers are used for this? Well, you also mentioned that the spectrum of rubidium is a deep red (also near infrared). What else uses deep red and near infrared light? Like all of 80s to 00s tech. Think CD players, TV remotes, etc. This means that all the needed tech to control rubidium is mass produced, and so is cheap, works well, and is efficient. In contrast, my friend in the lab across the hallway is doing sodium experiments, which requires amber lasers (think sodium street lights). She cant use a normal diode laser, and is instead using a dye laser, which is large, has flowing liquid (dye), and is a big pain to operate.

[@L1ama]

I thought the CD player diode laser wavelength (and the surprisingly good performance of grating-stabilized ECDLs, which can be "homebuilt" relatively cheaply) was going to be the point she was getting towards, lol. Lithium also has a commonly used resonance at 670 nm, which is close enough to the 650 nm diodes used in DVD players to benefit from the economies of scale there, and has both a bosonic and a fermionic isotope in naturally occurring samples (unlike Rb where both isotopes have fermionic nuclei).

[@pathutchison7688]

Wow. Great comment. Thanks for the insight. You answered about 3 or 4 questions I had that didn’t have to ask. 👍🏻

[@steveswartz1875]

I was also an AMO physics student in JILA in the 80s-90s. I would agree the ability to get laser light at 780nm and 778nm using diode lasers was a significant driving force in the earlier years for almost all work to be done being done with Rb (That and of course it was hydrogenic). The equivalent laser diodes at 850 and I think 852nm were just not widely available. For a long time the equivalent work with Cs which everyone actually wanted to do required an Argon ion pumped Ti-Sapphire laser. Compared to a diode laser it was an expensive finicky monster . I know, I built the first one in Dr Jan Halls lab at JILA.

[@Chance57]

Excellent bit of context!

[@thorwaldjohanson2526]

Rubidium is mass produced? Since when? All I ever saw was it being much more rare and expensive than cesium.

[@JosephFarina-r9s]

We use rubidium in the hospital! Rb-82 is a positron emitter with a physical half life of 75 seconds and is a decay product of the relatively longer lived strontium 82. Since rubidium is a potassium analog (and it’s produced in its own generator so no need to have a cyclotron on hand), it’s used in myocardial perfusion PET studies all the time. I bet it’s probably more used by hospitals than by all the physicists ha! 0:06 ❤ 0:06 If you have the chance you should look up Rb perfusion imaging and stress tests they’re super cool!

[@mp-zf4ur]

Thank you for the wormhole search I did on Rb perfusion imaging 🙃😄

[@TheReaverOfDarkness]

Hospitals so busy they never get around to updating the wikipedia page on rubidium.

[@JosephFarina-r9s]

@@TheReaverOfDarkness Rb-82 has its own wikipedia page and it's talked about more on there

[@Funkylogic]

I recall going in for a scan at the PA hospital in Brisbane and my friend whom was physicist told me a doctor there had designed a system to make CAT able to do PET scans. Got talking to the Radiologist and he told me a bit about the guy, said he was next level. Can't recall much more of it now, had a bit going on.

[@TheReaverOfDarkness]

@@Funkylogic Sounds doable. The data processing infrastructure would be the same, you'd just need to change out the detector plate along with the tracing agent which I assume are removable parts. After that it probably just takes a bit of slick recalibration to adjust for the difference in type of data received from the detector plate.

[@MFLuder-me1vn]

Angela I work in healthcare and have a medical degree. Several times there have been incidents where my patients have smoked while wearing supplemental oxygen and I can confirm that igniting your face is a bad thing.

[@ilovecuttlefish]

Thank you for confirming our suspicions that exploding your face is bad for you ❤

[@ax14pz107]

That's concerning, if true.

[@saikirannarayanaswami1618]

Why

[@elenna_alexia]

thank you for lending your expertise on this, we were all wanting to know.

[@ax14pz107]

@@saikirannarayanaswami1618 cigs are very addictive and it's super easy to absentmindedly light up a cig.

[@autumrnk]

So sad to hear of Dr. Collier's passing due to her interaction with Eric Cornell, glad she is still able to upload

[@marcogenovesi8570]

by the power of Rubidium she is still able to

[@GSBarlev]

The only thing that could make that story better would be Eric Cornell himself popping up in the comments like, "Hey Angela, been watching you for years. I totally remember that day, and I feel like such a jerk."

[@pendarischneider]

Is this some sort of Cornelian twist on a Pauli exclusion principle? Nothing personal it's just physics.

[@littledragon4792]

She got better.

[@pmcgee003]

It's October. It's literally a ghost story. 👻 😅

[@yourposer]

"I don't know, i'm not a doctor" - Dr Angela Collier

[@fariesz6786]

damnit, Jim, i'm a physicist not a physician!

[@davinderc]

It's dead and alive Jim!

[@rabbiboazmarmon7723]

She means that she’s not an “help! I’ve just exploded my face!” sort of doctor. But she absolutely is a “hey! How could I explode my face?” doctor.

[@craigmhamm]

@@justinclloydnot technically, literally!

[@akatsukami9578]

Ph.D. stands for "phoney doctor".

[@roriegilligan8134]

I'm a metallurgist. I worked on a project processing lepidolite (lithium bearing mica) to extract lithium. Rubidium was a minor component of the ore and a potential by-product. Cesium too. Both are found in lithium micas.

[@farzanroshdieh698]

Water is so readily available everywhere. How do these elements that go apeshit in water exist at all?

[@roriegilligan8134]

@@farzanroshdieh698 They don't occur naturally in the reactive metallic state, but as compounds with silicon, oxygen and other elements. I have a piece of cesium ore on my shelf which contains the cesium silicate mineral pollucite.

[@DoggMatik]

@@roriegilligan8134 same tbh

[@brockenglish7602]

"Don't lick it, your face will ignite. I dont know, Im not a doctor." lol

[@chad3814]

I mean in that other video she implied she was a doctor....

[@GSBarlev]

She clearly learned her lesson from the last video that she needs to put in disclaimers for that kind of thing.

[@AlanCanon2222]

She's so deadpan, I love it.

[@LimeyLassen]

I'd love to see a list of elemental cubes that ARE safe to lick.

[@davak72]

@@chad3814I hope this is a joke… She’s obviously a doctor in her field, but not a medical doctor, which is the assumed doctorate in the context of face ignition

[@steveswartz1875]

When I saw the title of this video I grinned about as much as anyone just getting over Covid can. I did my thesis work measuring the exact optical transition frequencies of Rb at JILA in the 90's so I was sure that for once I would have a good chance of following along trough the whole video without getting lost. I always enjoy your videos so would likeI thank you for covering this (kind of obscure?) topic. I was very fortunate to be a grad student at JILA while clever people were working out the details of cooling and trapping atoms and when success generating BEC condensate was announced everyone knew it was a big deal. I really enjoyed you little closing story about Eric Cornell.

[@sohl947]

I was at JILA also, albeit briefly (about June `89 through Dec.`90), part of Dr. Dana Anderson's group, across the hall from Dr. Wieman. My student office mate worked on that experiment for maybe two years... not sure he saw the BEC before he switched over to geophysics.

[@dakota9114]

As an element collector, thank you so much for the shout-out! It really is a fun hobby. I encourage anyone that might be interested at all to just jump into it! You would be surprised at how many elements are around you at all times! Edit: PLEASE DO YOUR DUE DILIGENCE AND RESEARCH SAFETY PRECAUTIONS PLEASE PLEASE PLEASE PLEASE PLEASE ELEMENTS ARE NOT TOYS MANY OF THEM CAN INJURE YOU PLEASE BE CAREFUL PLEASE Fun fact: Rubidium Nitrate is sometimes used in fireworks to give them a purple color, much like you might have heard of Strontium (Rubidium's next door neighbor) giving fireworks a red color!

[@canadiangemstones7636]

Best part is you can field collect a bunch of elements with a hammer and chisel, or metal detector, or gold pan. Stuff like copper, silver, sulfur, bismuth, even specks of gold are out there to be picked up. Find a local rock & gem club to get started.

[@RGAstrofotografia]

​@@canadiangemstones7636, just like Minecraft?

[@orterves]

​@RGAstrofotografia exactly the same. Be aware on the first day you'll want to dig a nice deep hole and then sleep in it that night, covered by the dirt, just to be safe. Though that might only be necessary here in Australia

[@cyborgninjamonkey]

I'm working on boron and silicon, going to do aluminothermic reduction. I'd love selenium but it's, as far as I'm aware, poisonous. It's not beryllium, but it fucks up proteins-unfortunate because H2SeO4 is incredibly useful.

[@RasielSuarez]

@@cyborgninjamonkey Neither selenium nor beryllium are toxic in solid elemental form. Keep it out of your body (that includes airborne particles) and they're harmless. Frankly, *any* type of powdered metal is bad news precisely because it's so easy for that powder to be breathed in where it can combine chemically into something nasty or by simply lodging in there scar the lungs (silicosis, carbon lung, etc.)

[@regrets...so.many.regrets.]

when i was a thin films deposition technician, i was always wondering 'why is it always ruthenium?', and i could never get a straight answer. so, it's comforting to learn that there are others out there not only asking the hard questions, but giving the straight answers.

[@Bialy_1]

On english wikipedia article the first info about Rubidium is: "Not to be confused with ruthenium."😅 But if someone want to read more about its uses in the world other versions of wikipedia articles are much more competent in this topic -> especialy russian.

[@christopherleubner6633]

It's used because it does not contaminate the stuff you want to deposit, especially oxides, arsenides, and sulfides (oh my) . The only other one that can be used for the same is even more costly rhodium. 😮

[@joelfenner]

Used to feel this way about Zirconium (first it was for the small neutron cross-section, and later it started showing up as a substitute for Cobalt in catalysts). A buddy of mine working at one of the national labs had a similar thing about Beryllium (amazing physical properties, x-ray transparency, etc.) as it kept creeping into his life and work much the same way. Sneaky elements trying to get closer to us. Probably for the kill.....I dunno.

[@christopherleubner6633]

@joelfenner One surprising use of zirconium is for the cathode assembly of very long life mission critical helium neon gas lasers. It's used because it absorbs nitrogen hydrogen and oxygen yet does not sputter much.

[@regrets...so.many.regrets.]

@@christopherleubner6633 yeah we also spttered rhodium, and those targets were worth about 50% of the company's physical assets.

[@snoogles007]

Minor update. You don't need to melt rubidium, or any other metal, to evaporate it. It's a really common misconception. Look at the vapour pressure curves of the elements versus temperature. You don't even see a discontinuity at their melting points. Most metal vapours are generated at lower temperatures through sublimation. The only time melting is useful is if you have a surface oxide you need to get rid of first to expose the pure metal.

[@albertorasa6220]

Nice video! Love how you can transmit your curiosity and emotions.

[@wallacegrommet9343]

That sounds so reassuring, until I think about the mercury in the fluorescent tubes I just broke

[@phillair3813]

What a natural teacher you are. I'm a retired secondary science teacher who enjoyed your conversational tone and obvious ability to get the point across..

[@yourbuddyben4854]

"Platonic best friend roommates" 💀😆 I love the and they were roommates thrown in so casually.

[@t.j.webster5545]

OH MY GOD THEY WERE ROOMMATES!

[@sadrevolution]

@@t.j.webster5545 So were my parents.

[@bubblesbomb8949]

​@@sadrevolution Yeah, what else is the answer for your conception?

[@kennethnielsen935]

lol this

[@physx-void-pointer]

Thank you Angela, please keep on with your videos, I've always enjoyed your content!

[@declanwilcoxon1123]

I just started my first year at CU Boulder and I got a chance to talk to Eric Cornell at JILA and he was amazing. So passionate about the work he was doing and he spent 20 minutes just walking me through it.

[@RoiHolden]

Never in my life did I think I would so enjoy watching a 20 minute video on Rubidium. You should do the whole Table!

[@carultch]

Especially while the OG, Yuri Oganesson, can join as a guest star.

[@АмиЛаза-г1ю]

one cool obscure use of rubidium is that its chloride can be used as a mood stabilizer just like lithium but unlike lithium it acts as a stimulant and not sedative

[@wewemcrhyne]

Wait, is this available for medical use? I’ve never heard of it. I’m a pharmacist and really want to know. Thanks

[@Blotchy]

​@@wewemcrhyne googled and found someone saying it used to be made under the brand name Rubizyme, though only a couple studies on PubMed about it which would make me nervous to take it if needed lol

[@GSBarlev]

@@wewemcrhyne While I found several research papers backing OP's assertion, it doesn't look like any formulations have hit the market. That said, I did find Rb-82 Chloride in a medication database, but its use was strictly as a radiopharmaceutical agent for PET scans.

[@hazeld8016]

Ayo i would love to have my mood stabilized while giving me energy. Too bad rubidium is rare (and also no one would prescribe it for me but that's boring)

[@zimbu_]

@@wewemcrhyne Nothing outside labs and a small number of small scale studies dating between 1970-2000 judging by a quick search. No P2.

[@thomasr7129]

Please keep these videos coming. I greatly appreciate your unique blend of science, anecdotes and dry humor - explaining various phenomenon in an easy-to-understand-manner. Thank you!

[@jacklamour2019]

I was with you all the way up to: "Have you ever been checking the physics archive..." but I love your videos 😃

[@orterves]

The dry, slightly sarcastic, but also earnest humour is always on point

[@nujuat]

@jacklamour2019 the sad thing is that I check the quantum physics arxiv all the time, actively looking for this rubidium stuff lmao

[@TheIndianaGeoff]

I can honestly say, I have never checked my physics archive.

[@spvillano]

@@TheIndianaGeoff really? I thought everybody did. I'm going to check with my apartment building maintenance guy, I think you guys are pulling my leg! Now, just where did I put my hat...

[@Celtokee]

Happens I’ve had an eccentric interest in Rb since the 90s. Here’s some arcane trivia. Rb is: • used by Italian researchers for treatment of depression/mania. • taken up by tumor cells in the place of potassium; it preferentially accumulates in tumor cells because they clear it much slower than normal cells. The Rb accumulation elevates tumor cell pH. • induces norepinephrine release from neurons to central adrenergic receptors. • required for serotonin synthesis, • Its deficiency depresses growth and life expectancy in goats. • required for forming disulfide bridges in enzymes • promotes release of hormone facilitators from the pituitary • required for activating procollagen hydroxylase, for proper collagen fiber formation.

[@Zandanga]

love mol cell bio, biomicrochem, histology, just so max cool down in the basement membranes 😎 thanks 👍

[@shigekax]

Guys I think I have a rubidium deficiency 🤒

[@PaulStoffregen]

At 13:20 no tech applications - rubidium is used in high accuracy oscillators where the best oven controlled quartz isn't good enough or where you can't depend on GPS signals to correct for the long-term drift that quartz tends to have.

[@willthecat3861]

Yes. Rubidium has been... and is being used... in clocks and oscillators. Atomic oscillators won't lose much time, over the long time... but atomic oscillators... like rubidium or cesium...are not suited to providing... in the short term... a very stable frequency. Quartz... even if the frequency has drifted, from the nominal... over the long term... Quartz has in the short term... a more stable frequency than atomic oscillators. Atomic oscillators have more 'jitter' than quartz oscillators. Combining the two kinds... either in an atomic clock... or just by GPS disciplining a quartz oscillator... is optimal.

[@peterbonucci9661]

I was ready to shout at the screen CLOCKS. We used Rubidium clocks for high accuracy timing. It was second best to Cesium, but we could afford it.

[@OnTheRocks71]

The Signal Path here on KZbin has a nice teardown of a frequency counter with built-in rubidium standard. I think that's where I (as a layman) first heard of such a thing.

[@Ardren]

On a consumer level, GPSDO are used in amateur radio. But there are many people using rubidium oscillators, some acquired, some old-new stock, and more recently, some just off Ali Express.

[@mezu-e]

I think maybe she meant it has no uses as a bulk or raw material

[@luciteria]

Thank you so much for the plug! 🤗

[@johnpienta4200]

If you can buy this kinda stuff, you definitely deserve it!

[@brendanmay9585]

I can't wait to unpack my new rubidium knowledge at the next party. ❤

[@pathutchison7688]

I know right? Whenever I’m at a party and rubidium inevitably comes up in the conversation, I always used to feel like an idiot. Not anymore. 🎉

[@learningisfun2108]

I’m sure the other party goers will be thrilled.

[@ciprianpopa1503]

wrap it well though, it always spills all over the place.

[@recklessroges]

Perfect KZbin video that I actually want to watch because Collier explains things with my level of enthusiasm, but with much more clarity and cool coffee shop anecdotes.

[@Rankin37]

That story about you meeting Eric Cornell in the coffee shop is my social anxiety nightmare 😭

[@ZweiZombies]

So mortifying.. we all died along with her

[@KarlBunker]

Meanwhile Eric Cornell is telling the story of how a gorgeous woman recognized him in a coffee shop and said "Oh my gosh, that's Eric Cornell!" and all he could think of to say was "Yeah ... hi ..." And later he died, and now he's dead.

[@DFGdanger]

RIP Angela

[@YayComity]

If I ever see Angela in a coffee shop I have to be prepared to say something better than "Oh my gosh that's Angela Collier!" What would be the most bestest thing to say? I have no idea. I'm going to lose sleep over this. Most of all it has to be spontaneous. Maybe "Hi Maria!"

[@sohl947]

My coffee shop moment was at Boulder when I bumped into Nobel-winning biochemist Thomas Cech at a near-campus restaurant (falafel IIRC?). I was a physics grad student and attended the same undergraduate college he did, so I had my opening line. Didn't know where to take the conversation, so it was brief. 😅

[@teds5408]

I work with rubidium and cesium clocks. I always wondered how the rubidium vapor cells and the rubidium lamp worked. This video provided a lot of insight into their design and manufacture. I will note that both rubidium and cesium have easily measured microwave emissions when the proper electron state change occurs. Now that optical technology has advanced to the point where the optical emissions can be used to synchronize clocks we are moving on to more accurate optical clocks, but rubidium is so low cost it will remain the work horse for years to come.

[@dannyslag]

I dont understand most of this, but i still enjoy listening to it.

[@michaelzumpano7318]

That was actually my favorite video of your’s. You made it like a mystery novel. And at the end you answered a bunch of questions we were probably all wondering about. Good work!

[@videomediamtl997]

But it left a lot of question marks about Francium 😅

[@pathutchison7688]

This channel is contending with “Steelers Depot” and “Historia Civilis” for the prestigious award, “Pat’s favorite Channel”. I hope I didn’t apply too much pressure on anyone who’s chasing such an amazing award. Edit: I also have to add “Time Ghost” and their channels “world war 2” and the “Korean War”. Best chronological documentary’s ever made.

[@Nikedemos]

who's pat

[@minerman60101]

@@Nikedemos the person whose comment you're replying to is pat

[@kevinbissinger]

​@@minerman60101 but then who was phone?

[@DunnoJustLuckyIGuess]

@@kevinbissinger Perhaps Pat was also phone and then a skeleton popped out

[@Corninthesky]

Historia Civilis 😍😍😍

[@alphgeek]

Great vid, thanks Dr Collier.

[@accomplishingnothing4246]

Hall of the mountain king is a great closing credit move

[@omarkos2112]

This video was so good!! As an undergraduate physics student who has come across almost all of the things mentioned in some (written) form or other, I found this incredibly helpful in piecing together key concepts and methods, even though the main point of the video is the consistency of rubidium usage. Keep up the good work!

[@UCXEO5L8xnaMJhtUsuNXhlmQ]

I had no idea what the video would be about when clicking on it but man what a great hook

[@thenonsequitur]

That's a good pretty description of most of her videos.

[@NeedForMadnessSVK]

"Have you ever been checking physics archive and..." No Angela, I am a dropout that never studied physics, I have never even seen a physics paper and I had absolutely no idea physicists love Rubidium that much. But I am still going to watch the video because it's interesting af.

[@mikerudin8261]

Another special thing about Rubidium that makes simple atomic clocks possible is the way energy levels differ between the two natural isotopes Rb85 and Rb87. The Rb frequency standard is based on the ground state hyperfine transition of Rb87 vapour in a glass resonance cell, i.e. two closely spaced levels 6.835GHz apart, and to measure that you need to pump a large fraction of the atoms into one of those levels, giving a population inversion like in a laser. That pumping is done using infrared light from a Rb87 vapour lamp which needs to be absorbed by only one of the resonance cell Rb87 hyperfine levels. However, the lamp light contains the same hyperfine structure as the test vapour, so one set of those hyperfine lines needs to be removed. Rb85 just happens to have a similar spectrum to Rb87 but shifted slightly in a way that makes it preferentially absorb one of the Rb87 hyperfine lines. So in practice a glass cell containing Rb85 vapour is used as an "isotopic filter" to absorb the unwanted Rb87 lines from the lamp. (The resonance cell and filter cell can be replaced by a cheaper single one with a mixture of Rb85 and Rb87, which still works well enough.) More details in NASA document 19700011280.pdf and Wikpedia "Rubidium_standard".

[@George-rk7ts]

Great work, Doctor Collier. And even more fun. And letting people see how much fun science is is awesome. You are an incredible you tuber.

[@HarryRT4UAndMe]

someone tweeted yr channel out on bluesky and as a nerd who studied ochem as an undergrad and regards my understanding of ~things~ too highly as a result - it’s so cool to watch fun, informative content like this from someone who knows what they’re talking about about and has a managed to get a comment section full of folks who are doing the same. I hope you’re able and willing to continue making Good Stuff 🙏

[@pahom2]

Atomic clocks are hell of an industrial application. Every single cellular base station has rubidium-disciplined crystal oscillator to drive frequency generator. Millions of them use tons of staff.

[@androgenoide]

GPS disciplined rubidium oscillator.

[@jamesdriscoll_tmp1515]

When I worked in a device lab, I swore they had a periodic chart on a cork board, and tossed darts to get a new element, just to miss with us.

[@77jaycube69]

I found cesium clocks to be easier to use.

[@androgenoide]

@@77jaycube69 Cesium clocks are considered the primary standard and rubidium clocks are considered secondary. The cesium is accurate by definition but the rubidium is cheap and used everywhere. In many cases the rubidium oscillator is disciplined by a GPS signal so it is effectively referenced to the cesium clock anyway.

[@pahom2]

@@androgenoide both GPS signals and rubidium feedback is used to discipline cristal oscillator. Rubidium itself doesn't oscillate in this device. It either pass waves or block them.

[@jimbryce6982]

Excellent. Absolutely excellent. I had just been discussing the use of rubidium in atomic clocks with a young engineering student, and now, Dr. Angela Collier, you have answered all our questions and many we didn't know we had. Thank you. The Nobel committee is watching you. 🙃

[@aardvarkpepper7660]

me: angela: why is it always rubidium? me: I need to know this. 🤔

[@davidspeirs1524]

Rb82 is being used in myocardial perfusion imaging. It's the daughter isotope of strontium-82, using a St82/Rb82 generator we can directly inject a patient with Rb82 (which has a half-life of 75 sec) and perform a stress test

[@spvillano]

They used technetium for my testing. Likely due to it being a hair more convenient and hence, cheaper. And that test was a hair more expensive for them than usual, as they had to switch from treadmill to chemical stress test after the treadmill was damaged trying to elevate my pulse enough for the test. They're really going to have to get better prepared for fitter over 60 types! Chuckle fest, resident radiologist ended up on the carpet over his report on the test. Hit the panic button unnecessarily over some mitral damage from when I had COVID, mistaking moderate for severe reflux. A hint for the actual severity, I broke the treadmill and right after the test, walked two miles to a supermarket usually out of my usual range to pick up 25 pounds of supplies not easily available locally, loaded them into my backpack, walked two miles back to ride my medical shared ride home. And cussed myself out for a couple of days. Damned dyslexia, I'm 62, not 26... ;) But, that lentil based fake meat loaf was worth the effort. Not vegan or vegetarian, just for a change of pace. Mild texture deficit though, next time I'll either add flax seed or more likely, oat meal for texture. Yeah, I do medical, built a cloud chamber because I was bored, same with a scintillation radiation spectrometer (OK, a bit crude, but works and is good for parties) and cook. And fix electronics when I'm bored, it's only physics, after all. :P Just like chemistry is. FOOD FIGHT!

[@roderos]

Making a real life periodic table with minerals and pure elements has been on my to do list for a while. Thanks for adding a story to Rubidium. We geologists use Rubidium isotopes together with Strontium for radiometric dating. It is especially useful in figuring out melting processes in the crust and mantle since Rubidium is very incompatible and rather stays in the liquid than build in a mineral.

[@NiallsSongs]

First timer to your channel. I looked at the duration before watching: "20 mins? I'll watch a minute and then follow up with some reading." Ended up watching till the end. Excellent stuff. Fantastic easy-to-get explanations without excessive down dumbing and most importantly, great sense of humour. ❤

[@aidanclark196]

I got to attend a couple collegues' dissertation defenses and one reason they used rubidium specifically was because I think its most common isotope doesn't have hyperfine splitting, which makes forcing a certain transistion they were looking for easier

[@tapiocaweasel]

it does, both 87Rb and 85Rb have hyperfine structure. honestly partly it was coincidence, Carl Wiemann used diode ripped out of cd players, and those worked with Rb. then Rb had (luckily) good elastic scattering properties that made evaporative cooling easy. but Li, Na, K, Cs, and even Fr are used in the first group. and anti-hydrogen at ALPHA, not sure if laser cooling on normally hydrogen is a thing people do... i should probably know that...

[@L1ama]

@@tapiocaweasel Ted Hänsch's group is working on cooling and trapping regular hydrogen, Dylan Yost at Colorado state is too. Maybe others as well, idk. The problem is that Lyman Alpha is a massive pain to generate and work with (attenuates quickly in air so you have to have a lot of your optics in vacuum, and even then every reflection loses somewhere in the double digit percentage level of power, maybe 30%? I forget) and even doing two-photon stuff at 243 nm isn't that much easier

[@jsalsman]

Rubidium is a gorgeous metal in raw form, especially when its rosy tint shows (not ingots.)

[@jjohansen86]

I have a PhD in AMO physics, and I worked on a Li-Cs (lithium-cesium) mixture experiment, and there's some additional detail to why Rb (rubidium) is favored: All the atomic physics techniques work well on it. There's a tendency for the lower mass alkali metals to have more trouble with the more advanced versions of laser cooling techniques, with lithium only relatively recently having "sub-Doppler" cooling methods ("sub-Doppler" meaning that these techniques can get your atoms even colder than the most basic laser cooling technique) implemented for it. So from a laser cooling perspective, Rb and Cs are the best. However, for the very lowest temperature experiments (where fun quantum effects and interactions really come into play, rather than just being dominated by thermal effects, so that's where you usually want to be), you need to do some additional steps, and the easiest way to do this is in a "magnetic trap," which, as its name implies, involves magnetic fields. The problem with Cs is that it does some crazy things as you change the magnetic field, a really cold gas of Cs atoms is only stable at very specific magnetic fields, so you really can't do magnetic trapping with Cs atoms. That leaves Rb as the best candidate for basic atomic physics experiments, so you have to have a really good reason for using something else (maybe the magnetic craziness of Cs is something you want to use for your experiment, or the low mass of Li makes a difference, or something like that), because using something other than Rb makes your experiment more difficult and complicated.

[@gabor6259]

Congratulations for 200k subs! 😊

[@kwi5331]

Thanks!

[@ToolA10]

@acollierastro My friend was on that JILA team in 1995. I sent him your video. He said: “I think she should also have mentioned that Rbs lowest transitions match up with the wavelength of standard diode lasers and its magnetic hyperfine transitions are at convenient microwave frequencies. We have the right flashlights to look at rubidium…” 😂 Took the words right out of my mouth.

[@martineverett5061]

Say no more!

[@spvillano]

True enough, compared to sodium and now, one's a plumber for a dye laser. Here, common diode lasers are inexpensive and excellent excitation sources. And everybody loves to excite their electrons! Microwaves also being much easier to work with, compared to a couple of generations ago and horrific to work with back in the 1940's and '50's. And precision equipment is now far cheaper than ever before in human history!

[@BlueBearOne]

I really appreciate your channel. And it's not because you are beautiful, lol. I like the way your mind works, how you frame your curiosity, and you explore it, and how you present it to other like minded people. You are a great teacher! Thanks for all your hard work.

[@paulsidhuUK]

Worth watching to the end for a funny story!

[@dahawk8574]

Today he spots Angela and says... "Omg, that's Angela Collier."

[@RookFrjosa]

This girl is SO cool! Thanks for all the work you've put into your channel, Angela!

[@cyclonasaurusrex1525]

I wonder if Eric Cornell ever tells the story of that time in a coffee shop when . . .

[@mist3h]

💀💀💀

[@RealDevastatia]

I suspect Mr. Cornell is too modest to boast about the time he resuscitated a dead woman.

[@vindik8or]

RIP in piece

[@GSBarlev]

You gotta think that it's only a matter of time until some current or former student of Cornell forwards him this video... assuming he's not already subscribed. 💀

[@lurkmoar3926]

Angela, that was an extremely interesting, clear, and well delivered lecture. 👍

[@Alpine_Forensics_Locating]

I have a high-end audio interface made by Antelope Audio. This unit records and plays back digital audio. It uses a rubidium clock that is heated to a specific degree. Rubidium is used due to the stability of the release of electrons. If you read your physics papers where rubidium is discussed, you will read things that hint at frequency/wavelength/stability. Thinks like "frequency" or "stability" or "jitter" relative to digital audio. A more accurate element, used in at least one mastering house's custom digital clock is plutonium. The danger of plutonium makes it impractical in most cases, and you need a waver from the department of Defense to even have it in your possession, so that is why rubidium is used in its place.

[@RealDevastatia]

I've heard of golden ears. Yours must be platinum.

[@tim57243]

​@@RealDevastatiaGold costs more than platinum, lately.

[@lawrenceleske3470]

Since the human ear can maybe detect jitter of 1 microsecond (unpublished experiment) rubidium clocking may be a bit over kill.

[@L1ama]

Yeah that is several orders of magnitude of overkill and completely imperceptible to any human, and a borderline scam. It's also not "the stability of the release of electrons" that's utilised, it's the linewidth of the rubidium hyperfine transition. Caesium clocks are more precise than rubidium ones, and hydrogen masers also have their place in the top end of the hierarchy, beyond that you're getting into research-level optical lattice clocks and ion clocks. I have never heard of anyone even proposing a plutonium atomic clock, that sounds like complete snake oil. A decent OCXO (oven-controlled crystal oscillator) will get you part-per-billion accuracy and is typically better for jitter (which is what actually matters for digital audio, no one on earth is going to notice a pitch being off by a part per billion) than an atomic clock. Atomic clocks aren't the best on short timescales, they shine when you can run them for a long time and average them down.

[@Flapjackbatter]

Rubidium oscillators are altso used in cellphone tech. From what I understand each base station contains one such oscillator. And they have a life of only so so many hours, after wich they are no longer to be relied on. And they are then sold. You can find them cheap on auction sites.

[@marc-andrebrunet5386]

I incline myself in front of your questioning mademoiselle ! Everything you talk about is interesting.. I mean absolutely everything 📡 J'ai un énorme respect pour votre manière d'interpréter, d'expliquer et de vulgariser les choses très complexe de la science physique de manière à ce que les gens ordinaires comme moi, puisse trouver une manière de comprendre. Rubidium is a very cool element😊 My favorite part on this video is the last minute✌️😄 Merci

[@Corndog1]

This video brought back all the trauma I have from my chemistry undergrad and my physical chemistry lecture. Thank you, all hail Rubidium.

[@alanguile8945]

I love the way that you answer the questions that come to me during the talk! Thanks for your amazing ability to make anything interesting!

[@robotlandscape]

I'm like Rubidium: not a lot of uses in the real world, really good at physics, and explodes violently on contact with the outside world

[@JosephFarina-r9s]

We use rubidium in the hospital! Rb-82 is a positron emitter with a physical half life of 75 seconds and is a decay product of the relatively longer lived strontium 82. Since rubidium is a potassium analog (and it’s produced in its own generator so no need to have a cyclotron on hand), it’s used in myocardial perfusion PET studies all the time. I bet it’s probably more used by hospitals than by all the physicists ha! If you have the chance you should look up Rb perfusion imaging and stress tests they’re super cool!

[@CrushOfSiel]

"Have you even ever heard of Rubidium?" I did my 8th grade science project on it :D. All I remember is it is very reactive.

[@Arigatoster]

Angela's videos are rare occasions when i want to like it more than once

[@wiadroman]

Angela: But don't just lick rubidium. Me: Thoo laythe

[@ivanborsuk1110]

are you ok? i'm worried

[@spvillano]

@@ivanborsuk1110 everything's fine, farted it right out.

[@jforozco12]

love your presentation style! please do more sci fi geeky videos too, your star trek breakdown was fantastic.

[@johnwest7993]

I keep rubidium in my electronics lab all the time, though it's completely inaccessible. It's important to me, as it is the heart of my rubidium frequency reference. If only I had some cesium in a similar reference.

[@daverooneyca]

Man, I've been out of physics for almost 40 years and this video made perfect sense to me. Nicely done!

[@survivorchallenges]

NEW ANGELA VIDEO, LETS GO!!!!!!!!!!!!!!!

[@zamplify]

Where we going

[@RLanceHunter]

Woot! Gonna learn something today!

[@brendanmay9585]

Yay! 🎉🎉🎉

[@FPSIreland2]

@@zamplifyto watch the video

[@jaredcarlyle4398]

We are blessed this day

[@Chris-uh1ty]

Love your personality. Do more Star Trek. Take any angle. Do physics, do episode reviews and thoughts. Do deep dives. Anything. Your Picard stuff was chefs kiss. Anyway, guess I'll get back to learning things I don't know yet. (Listenting to this video).

[@vindik8or]

0.05% abundance in the crust would be very, very high. That would make it more abundant than carbon. It is in fact one of 58 elements that together make up 0.05% of the crust, itself clocking in at 0.009%. That does, however, make it more abundant than a bunch of other important metals like zinc, copper, nickel, lead, tin, and tungsten.

[@dropped_box]

I bet you both get your info from Wikipedia. Only she doesn't read very thoroughly.

[@vindik8or]

@@dropped_box I certainly did, I assume that's what happened too. I knew on hearing it that 0.05% was way too high and checked Wikipedia to confirm where I saw that same number in the article but with the additional info.

[@byebbyeb1219]

i love that you got and showed the rubidium cube!! i was absolutely floored when luciteria added it, i never expected they'd actually make one bc of how soft, reactive, and melty it is lol 😅 i was so excited to get mine and i love showing it to people, especially since most of them have never heard of rubidium before 😁

[@JarheadCrayonEater]

I used to calibrate rubidium oscillators using cesium oscillators for Lockheed, among other equipment as a former Metrologist.

[@77jaycube69]

We did the same for satellite comms. Well, not for Lockheed but another organization.

[@JarheadCrayonEater]

@@77jaycube69, awesome! Ours depended on the customer as to the application, but had several satellites pass through since we had several clean rooms for them. Others used them for phone development and manufacturing. Seems like yesterday, but it's already been 20 years!

[@codefeenix]

[REDACTED]

[@JarheadCrayonEater]

@@codefeenix, China?

[@twalker166]

I'm an AMO physicist who's never actually done experiments with Rb, but every lab I've worked in has used it for something related to the experiment, mainly as a frequency reference

[@IainG10]

I'm am unreasonably happy to see hydrogen at the top of that Group 1 column; almost every Periodic Table I see has it up on its own in the top centre. Like, yes, it's also halide-like (i.e. missing 1 electron for a full shell), but whilst alkali metals increase in reactivity as you go up in mass, halides decrease in reactivity, and hydrogen is by no means more reactive than fluorine (but it is less reactive than lithium). Also, In the Hall of the Mountain King is one of my favourite pieces of non-modern music!

[@Winspur1982]

1. I'm not well-versed in chemistry. I kind of thought hydrogen was on its own in most periodic tables because it's so common across the universe. Or because it's a sort of relic from ancient / medieval science, when water was assumed (perhaps) to be the most common element. 2. I love Grieg as a composer. It's amazing what composers could do when they had to create music for plays, as that piece originally was.

[@johngage5391]

I can't explain why I like knowing things like this, but thank you, Angela!

[@xenotimeyt]

Another important thing for certain experiments (especially neutral atom quantum computers) is that Rubidium forms a closed optical loop There’s two ground states |0> and |0*> and two respective excited states |1> and |1*> Oftentimes you want to have only one ground state |0>, which for Rubidium you can get by just exciting it and letting it decay, since the |1*> state usually decays not to the |0*> state but to the |0> state Great video tho, all hail rubidium :)

[@tapiocaweasel]

cycling transitions, or rather the lack of them, is the bane of most laser cooling efforts in most atoms/molecules/isotopes

[@throckmortensnivel2850]

Another very interesting presentation from one of my two favourite physicists. Thank you for all the work you put into this.

[@tapiocaweasel]

because rb is easy. i haven't used rubidium since my first couple years at JILA tho. its because the s-wave scattering length is ~100 a_0 (if you need collisions for evaporative cooling), and 780 nm is convenient diode wavelength

[@theaizere]

Hello, I'm a highschool student. By convenient do you mean easy to detect? Best wishes

[@tapiocaweasel]

@@theaizere its reletivly abundant, which is nice. it's main transition is at 780 nm, which is convenient because diode lasers are cheap at that wavelength. its also magnetic, which is good sometimes. for the first BEC they used a magnetic trap, so you need a magnetic dipole moment. It also has good scattering properties, when two Rb (87) atoms hit each other don't tend to stick together (Rb85 does stick together). its also has a high vapor pressure, so you can get atoms in your vacuum chamber without too much work compared to strontium.

[@theaizere]

@@tapiocaweasel Thank you for such detailed and thoughtful explanation! Have a great day :)

[@georgegonzalez2476]

Remember the color TV's of the 1970's through 1990's? The colors were encoded into the TV signal as the phase of a 3.587545 MHz signal. It was super important that this phase didn't wander, so the networks and individual TV stations all had a rubidium frequency standard so they all stayed on the same page, er, phase. Before that the TV colors tended to wander as just a fraction of a nanosecond of frequency drift would add up over time into major color swings. You can thank Rubidium for having stable TV colors when watching Saturday morning cartoons.

[@Lykrast]

fun rubidium fact: Rubidium is a minecraft mod that is an unofficial port of the popular optimization mod Sodium to the modloader forge (as sodium runs on modloader fabric)

[@smsiv]

Neither fun nor a rubidium fact

[@galoomba5559]

is there a Potassium mod

[@GSBarlev]

​@@galoomba5559Potassium is a *modpack* based around Sodium that serves as a drop-in replacement for the does-it-all Forge mod Optifine

[@GSBarlev]

@@galoomba5559 It's a *modpack* built around Sodium, so: sort of.

[@Lykrast]

@@galoomba5559 no :(

[@whatevil]

Just discovered your channel and have watched a few vids and subscribed. Congrats on 200k subs!

[@beegman27]

3:00 "platonic-best-friend-roomates" got me GOOD XD

[@GSBarlev]

Roscoe being cropped out of the picture was a vicious callback.

[@eismccc]

Thanks for the Luciteria link; I had the idea of a periodic table with the actual elements when I decided to commit the elements and thermal characteristics to memory when I was a kid, and now I can go broke realizing that very original idea :)

[@SciHeartJourney]

I used to work for a company that makes high grade pressure switches for the aerospace industry. My boss was this brilliant man telling me how we could improve that product using rubidium. He told me it has a very hard surface, so the contact wear is a lot better. Earning my MSEE I learned about AFM's, TSEM's and etc. AFM's are rather amazing because they actually touch or nearly touch the surface of what you're looking at. There are many things you could sense by at the atomic level!

[@johnhawkinson]

Rubidium as a switch contact? Not Rhodium?

[@dean.mcmxcvi]

Your humor is consistently the best on KZbin :) lol

[@Vort_tm]

Our SI unit for time is based on Cesium. So it's *ALMOST* always rubidium! BOOM - Scienced!

[@zenmark42]

You're really good at science communication. That was so fun and well structured and while I hadn't seen the other videos mentioned your explanations were great and the whole video was super good at being self contained to understand the "why rubidium" question. Also your story at the end was uh maybe a bit relatable.

[@WilliamRoyNelson]

You said "What we just learned about rubidium does not explain anything about why physicists would just love to have rubidium around all the time" *right* after showing that it explodes if you drop it in water.

[@JuneWebb-i3l]

Love is never lost. If not reciprocated, it will flow back and soften and purify the heart.

[@Moojuice4]

09:35 Reminds me of simplifying complex electrical circuits using Thevenin's and Norton's theorems.

[@Facetime_Curvature]

You're triggering me bro

[@Ladco77]

"Have you ever been checking the physics archive and just scrolling through the AMO physics papers....?" It was at that moment I realized I did not have the education background to fully appreciate and understand this video, but it's still fascinating.

[@culwin]

Seinfeld: what's the DEAL with Rubidium?!

[@kitten_processing_inc4415]

I like your joy combined with your expertise.

[@AbuMohandes-p2c]

Old physics dog here. Young talents like yourself give me hope for the future. Very brave to inflict your audience with Schrodinger's equation in detail :-)

[@TCook-d3s]

200k subscribers! Girl you’re kicking arrrss. Keep up the good work.

[@tommihommi1]

I'd say rubidium clocks are a useful technical application... but simultaneously kind of a quantum physics thing.

[@nickc3657]

I was about to say you should do a Luciteria sponsorship just based on the thumbnail! Their blurbs for each element are so fun ❤

[@jrussino]

0:10 I know of Rubidium from that one Tom Lehrer song

[@dougmorgan6616]

My first time visiting your channel. I love your presentation style.

[@kurtmayer2041]

hall of the mountain king seems like exactly the correct music for this cursed approximation

[@ps.2]

Call me basic but I don't think I will ever get tired of that piece.