SGU Episode 877: Difference between revisions

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== News Items ==
== News Items ==


'''S:'''
=== Redefining the Second <small>(10:27)</small> ===
* [https://www.nytimes.com/2022/04/25/science/time-second-measurement.html Get Ready For the New, Improved Second]<ref>[https://www.nytimes.com/2022/04/25/science/time-second-measurement.html NYT: Get Ready For the New, Improved Second]</ref>
 
'''S:''' All right guys let's move on to some news items. And Jay you're gonna start with redefining the second. So this is another series of news items about measurements and stuff, whenever there's a significant update to measurements we like to talk about it. this one this time it's the second.
 
'''J:''' This one has a really cool history to it, there's so much more here than I could cover. Look, scientists are about to do something big, to something very small, right? Seconds, right they're small Cara, but they're important. The second is important. So they're gonna change the definition of the second. And I don't mean like we're going to call it something else. They are refining the accuracy of the second and let me tell you the story behind it. Now historically people would track time by the Earth's movement. This is what people have been doing for thousands of years. The Sun's relative position would change in the sky, right? And since the Earth's rotate rotation is slowing, which it factually is, scientists knew that they had to measure time in a way that was considered to be a 100% constant, right? Because the Earth, the Earth's rotation is slowly, slowly slowing down, that means that the amount of time it takes the Earth to rotate is changing. And that's not good when you're tracking seconds and when seconds or even hundreds of seconds or thousands of seconds are important to do scientific measurements. So for example Earth, Earth's slowing rotation lost three hours of time in the past two thousand years. Now I get that that might not seem like a lot but, but to science it's intolerable! Like, right, scientists can't stand that it's not, it's not a predictable measure of time because you know one second is changing if you, if you use that, if you're measuring it via the rotation of the Earth. So, I recommend that you read some history of the way that humans have been tracking time and how time tracking came to be because it's fascinating. But to give you a tiny little bit of information, before 1967 the second was considered one over eighty six thousand four hundredth of a day. That was, that's that was basically what you needed to know. And all this led scientists back in '67 to change how we measure time by looking, now instead of saying we're going to use the Earth or astronomical ways of defining how long a second is, we are going to use atoms, right? Like an atomic clock, I'm sure you've heard of the term atomic clock. Well what the hell does that mean? What is an atomic clock? Scientists needed something back then that was predictable and more constant than the rotation of the Earth. So they used the motion of atomic particles, because they never wear out, right, you know atoms don't wear out. And they never change their properties. Atoms are going to behave the way that they are at the speed that they're going to behave under normal conditions and that's it forever. Until the universe ends so from a scientific point of view, they are the perfect way to measure time. Using atoms and using the movement of atomic particles. So they ended up using, they ended up using something called cesium which you know it's it's an atom.
 
'''C:''' It's an element.
 
'''J:''' It's an element.
 
'''C:''' It's weird to say it's an atom.
 
'''J:''' Yeah, you're right, it's an element made of atoms. Okay. So because that, because cesium, they have a heavier atomic weight and it's its resonance frequency was easier to study and track. They use microwaves to excite the cesium atoms to emit a flash of light at regular intervals and those regular intervals were the movement of the atom itself. They had instruments that could pick up the flash of photons and measure time using these regular flashes that that came from the atom when they hit them with microwaves, right?
 
'''B:''' Right so like 9.2, 9.2 billion flashes in a second.
 
'''S:''' Yeah.
 
'''B:''' So that number is very precise.
 
'''C:''' How do you count something like, how do you have the resolution that counts something like that? ''(laughter)''
 
'''S:''' Okay, I think, I think I can give a more technical explanation than that. It's tricky and it's hard to find sources that really give it a good description, but here we go. Cesium-133 atoms essentially exist in two energy states, let's just say a low energy and a high energy state. So they use a magnet to separate the two, so that you have a pure stream of low energy state cesium atoms. They then expose it to microwaves at precisely the right frequency, that 9.2 billion cycles per second which bumps the low energy cesium items into a high energy state. They then use another magnet to remove any remaining low energy cesium atoms and they count the high energy cesium atoms. Which then feeds back into the microwave generator so they can fine-tune the microwaves to the precise frequency that maximizes the number of high-energy cesium atoms hitting the detector, right ? So that's how they make that that frequency extremely, extremely precise. Here's where it gets a little tricky and it's hard to find an exact description. I think there's different types of clocks that may use different methods but a common method at this point is then to use a quartz crystal, like a regular quartz time keeper. And they use the resident frequency of the microwaves to fine-tune the oscillations of the quartz crystal. In one description where they get they make it 10 million cycles per second. And then you can just use regular electronics to measure those 10 million cycles per second. Basically every 10 million cycles it spits out a pulse, that's one second. So but I know there's a, there's a [https://www.nist.gov/pml/time-and-frequency-division/time-realization/primary-standard-nist-f1 Fountain Cesium Clock at NIST] which is uses a slightly different method. It gets a little technically complicated at that point but it's essentially they're fine tuning the resonance frequency of the microwaves to the cesium atoms by measuring how many of those atoms get bumped into the higher energy state and then they have to feed that back into some kind of counter which could in one type uses just a regular quartz crystal to measure time.
 
'''J:''' All right so guys the [https://www.bipm.org/en/home International Bureau of Weights and Measures] which I think is pretty cool. They ended up facilitating the official change in measuring the second using these cesium atoms back in '67. But keep in mind that astronomical time and atomic time still needed to be synced up since we're living on Earth and we need to we need our, you know, our day and night and our 24 hour cycle to still make sense, even though it's a little bit longer than 24 hours, they still had to sync them up. So what scientists did is they add a leap second to the atomic time roughly every year and a half. And this accounts for Earth's slowing spin.
 
'''C:''' And this is why like our GPS's work?
 
'''J:''' Yeah right.
 
'''S:''' Part of it.
 
'''J:''' If they didn't if they didn't sync things up like this lots of stuff wouldn't work, right? So they have to they have to sync it up because we are bound to the Earth and we live on the Earth so therefore we need our astronomical time keeping and our atomic time keeping to jive with each other so we have these fix it, fix it little doodads that we do every year and a half or so. So updating the measure of a second is happening because scientists have created new and very sensitive instruments called optical atomic clocks. these work like the cesium time tracking method but the new version can detect much faster atomic movement. So they can, they can use many different atoms today or ions with the latest equipment that they've come up with like like strontium and mercury and aluminum, to list a few. Now none of them have been picked as the new default atom or ion because all of the this is still in the laboratory, it's not ready for prime time yet, you know, they haven't dialed everything in yet. The equipment takes many people to operate, you know, it's not, it's not simple enough or elegant enough to use as the new standard yet. The equipment takes many people to operate and is simply not elegant enough to use as the new standard yet. The equipment needs to be perfectly stable as an example it has to be shielded from the Earth's magnetic field, you know, they need to chill the atoms or ions to near absolute zero. This slows them down and then they shoot lasers at them. And they're searching for the best wavelength of light that works best with each different atom or ion, right, because they want they want that really specific wavelength of light that's going to make the atom do something, like give a predictable reaction. Like it might create photons or you know it might you know give off a certain amount of energy at some at some point that they can detect.
 
'''S:''' Yeah so essentially they're using atoms that have a resonance frequency in the optical range rather than the microwave range. So they're, that resonant frequency is about 50 000 times greater than for cesium atoms and therefore they're 50 000 times more precise.
 
'''J:''' A second type of laser called a [https://www.nist.gov/programs-projects/femtosecond-laser-frequency-combs-optical-clocks Femtosecond-Laser Frequency Comb]
 
'''B:''' Oh baby. 
 
'''J:''' This is what Bob uses in the morning to comb his hair. A Femtosecond-Laser Frequency Comb. This laser is used to read the wavelengths of laser light that excites the atoms or ions. So this process can detect and measure these pulses of light a hundred thousand times faster than the cesium clocks from 50 years ago.
 
'''E:''' Whoa, that's, that's significant.
 
'''B:''' Nice.
 
'''J:''' Right? So that right there is how much more accurate the clocks, you know, the atomic clocks are today than the ones that they created back in '67 or earlier. This means that these new methods of measuring time are are just much more accurate and much more in line with scientific precision. Which is what we want here. So, after all this I would expect at least Cara or Evan to say, hey why do we need the second to be so much more precise? Who cares?
 
'''C:''' For our GPS's
 
'''E:''' Hey, why do we need the second to be so much more precise?
 
'''J:''' Thank you Evan, I'm really glad that you're absorbing this. One reason is that time is affected by gravity.
 
'''E:''' Is it?
 
'''J:''' And you might go okay so what. Well time moves slower when you are near a planet or a black hole, right? So the closer you are to a gravity well, anything that is producing gravity, could be a planet, could be a Sun, could be a black hole. Time is not constant in our universe because of this. Time is constant to the, you know, to your relative position but time is moving faster and slower all over the place in our universe because of gravity. Because atomic clocks are affected by gravity and their time tracking will reflect this, this means that they can detect things like gravitational waves or dark matter. Think about that. Right? Because they are, they're so sensitive to changes in gravity, these these new atomic clocks. They can detect gravitational waves, that is freaking amazing. This was proven back in─
 
'''C:''' Would they be used for that purpose?
 
'''J:''' I absolutely think so Cara, I mean I think that they're so sensitive
 
'''B:''' Wait a second, wait how did that work?
 
'''J:''' I'm gonna tell you right now Bob, I'm gonna tell you right now, check this out, this was proven back in 2015. So physicists at NIST were working on these optical atomic clocks and they noticed that the time was not consistent on all their clocks that that were situated around boulder Colorado. They have multiple, multiple versions of these clocks that they're, that they're working on and that they're testing and they were very close to each other all, you know, all in the same city. But the time that they were representing was off and they're like what's going on, what the hell is this? So it turns out that all the clocks were at slightly different altitudes.
 
'''B:''' Yes! Right.
 
'''E:''' The altitude matters?
 
'''J:''' So why does that matter? A clock that was one centimeter higher than another one, that was a few miles away was reading time differently because it was farther from the center of the Earth which means that it was farther from the center of the gravity well that it was pulling on it. One centimeter guys. And they, and these these clocks recorded the difference.


'''B:'''
'''B:''' All right, so...


'''C:'''
'''J:''' One centimeter in altitude, Bob, think about that.


'''J:'''
'''B:''' I already have, I talked about it like a year and a half ago on this show.


'''E:'''
'''J:''' What did you think, what was your reaction?
<!-- ** the triple quotes are how you get the initials to be bolded. Remember to use double quotes with parentheses for non-speech sounds like (laughter) and (applause). It's a good practice to use brackets for comments like [inaudible] and [sarcasm]. -->


''(laughs)''
'''B:''' You said gravitational waves Jay.
''(laughter)''
 
''(applause)''
'''J:''' Yes. They said, Bob, the article said that these things could detect gravitational waves and dark matter.
[inaudible]
 
'''S:''' Bob, Bob, I think this is what jay's talking about. So I'm seeing a study from 2015 "Using Atomic Clocks to Detect Gravitational Waves" they say that if we they, they're pointing out theoretically, that if you had an array of atomic clocks distributed along the Earth's orbit around the Sun, that that would have the sensitivity to detect the time dilation effect of a megahertz gravitational wave. Such as those emitted by supermassive black holes and binary. So you would have to set up an instrument using these clocks to detect it.
 
'''C:''' Yeah.
 
'''S:''' You're detecting the difference you know between an array of these atomic clocks but they are sensitive enough that they can detect something of the magnitude, the relativity effect of the magnitude of a gravitational wave.
 
'''B:''' So I'm just trying to think how, how it stretched space time by like, by like a thousandth of the diameter of a proton, how that is going to affect an atomic clock.
 
'''S:''' The simultaneous measurement of clock rates at different phases of a passing gravitational wave provides an attractive alternative to the interferometric detection of temporal variations in distance.
 
'''C:''' Yeah it sounds like it's not the clock itself, it's the clock relative to the clock next to it.
 
'''B:''' Yeah yeah, so yeah, oh yeah of course, of course, but okay all right, I get, I get that. But I mean, that just just that just came out of left field for me.
 
'''J:''' They're saying that it's possible that they will have like have finalized this way of measuring time, probably by the second half of this decade. You know, They're, I don't think they're in a big rush. I think they want to wait until they nail it.of course.
 
'''S:''' Yeah they have time. ''(laughter)''  
 
'''J:''' But. But we will be someday very soon, we will be measuring, we will be measuring the second now with more precision, you know, once that they master this technique. So nothing has changed other than the fact that it's more accurate and that it can do a lot of cool things that piss Bob off.
 
'''S:''' Okay all right thanks Jay.
 
'''C:''' Love you guys.
 
'''B:''' Love you Jay.


=== Redefining the Second <small>(10:27)</small> ===
* [https://www.nytimes.com/2022/04/25/science/time-second-measurement.html Get Ready For the New, Improved Second]<ref>[https://www.nytimes.com/2022/04/25/science/time-second-measurement.html NYT: Get Ready For the New, Improved Second]</ref>
=== NFT Medicine <small>(24:24)</small> ===
=== NFT Medicine <small>(24:24)</small> ===
* [https://www.theverge.com/2022/4/26/23042736/go-read-this-nft-clinic-medical-advice-metadocs-metaverse Go read this report about the virtual doctors at an NFT clinic who can’t legally give medical advice]<ref>[https://www.theverge.com/2022/4/26/23042736/go-read-this-nft-clinic-medical-advice-metadocs-metaverse The Verge: Go read this report about the virtual doctors at an NFT clinic who can’t legally give medical advice]</ref>
* [https://www.theverge.com/2022/4/26/23042736/go-read-this-nft-clinic-medical-advice-metadocs-metaverse Go read this report about the virtual doctors at an NFT clinic who can’t legally give medical advice]<ref>[https://www.theverge.com/2022/4/26/23042736/go-read-this-nft-clinic-medical-advice-metadocs-metaverse The Verge: Go read this report about the virtual doctors at an NFT clinic who can’t legally give medical advice]</ref>
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{{anchor|futureWTN}} <!-- keep right above the following sub-section. this is the anchor used by the "wtnAnswer" template, which links the previous "new noisy" segment to its future WTN, here.
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== Who's That Noisy? <small>(1:14:30)</small> ==
== Who's That Noisy? <small>(1:14:30)</small> ==
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Revision as of 00:46, 16 July 2022

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SGU Episode 877
April 30th 2022
877 LHC 2022.jpg
(brief caption for the episode icon)

SGU 876                      SGU 878

Skeptical Rogues
S: Steven Novella

B: Bob Novella

C: Cara Santa Maria

J: Jay Novella

E: Evan Bernstein

Quote of the Week

There is an urgent need today for the citizens of a democracy to think well. It is not enough to have freedom of the Press and parliamentary institutions. Our difficulties are due partly to our own stupidity, partly to the exploitation of that stupidity, and partly to our own prejudices and personal desires.

Lizzie Susan Stebbing, British philosopher

Links
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Show Notes
Forum Discussion

Introduction, Surgery Recovery

Voice-over: You're listening to the Skeptics' Guide to the Universe, your escape to reality.

S: Hello and welcome to the Skeptics' Guide to the Universe. Today is Wednesday, April 27th, 2022, and this is your host, Steven Novella. Joining me this week are Bob Novella...

B: Hey, everybody!

S: Cara Santa Maria...

C: Howdy.

S: Jay Novella...

J: Hey guys.

S: ...and Evan Bernstein.

E: Good evening everyone!

S: How is everyone.

B: Good good good.

C: I am recovering.

S: Recovering from what?

C: From surgery.

B: Yeah, that's right.

C: I had surgery last Thursday and I'm feeling almost 100% now, I'm definitely have, my appetite is back, I had no appetite for two days, I was super queasy post anesthesia. I'm not quite as weak as I was. I was very weak the first few days, I was sleeping an awful lot. And my head felt really buzzy and just off man, anesthesia sticks with you for a while.

S: Oh yes.

J: That's no joke.

B: That's not normal though, you have, you're, I think it sounds like you have more of an extreme.

C: No, it's pretty normal for total anesthesia. I mean it's why they give you in your discharge instructions like don't operate, you cannot drive today, you shouldn't shower until tomorrow and even then you should take it easy. They say I couldn't lift anything more than five pounds. Ii definitely remember like two days after I got a new carpet cleaner and I got so excited and I cleaned some like spots that Killer had left on the carpet. And it exhausted me. I needed a nap after I cleaned the carpet.

S: Well you know what Bob, you know, part of the reason is so it definitely gets worse with age. And that's just you know the brain.

C: Oh yeah, if you, if the last time you went under you were young, you probably wouldn't.

S: But, there's some pharmacological reasons for that too, I don't know exactly what drugs they gave you or how much or whatever, but when you get, when you get a lot of drugs for that are sedating, because you had prolonged anesthesia or you've been in the hospital for a while getting those kinds of medications. Some of them are fat soluble so what happens is, they give you enough to have a clinical effect, so there's a certain amount in your blood, but in order to achieve that a lot of it gets distributed into your fat. And then over days and weeks that the medications come out of your fat back into your blood, so even though you're not taking the medications anymore it could take days and days for it to clear it out of your system.

C: Yeah some of some of my aftercare said two weeks to be careful about this kind of stuff. And granted for me it was about two-three days but I mean, I remember I couldn't really watch TV. Like, I was like, oh, I'm gonna have a couple days off, I'm just gonna lie about and watch TV and I was like, I can't focus, it's like eyes are crossing. But, but, to be fair I was only under for an hour and a half.

S: Yeah, that's not too much.

C: So I didn't have terrible anesthesia but I do think I was propofol and I had versed which, you know, was like anti-anxiety medication and a fair amount of like zofran and pepcid like things to keep me from barfing, thank goodness, because I didn't barf. But I do think that there are different anesthesia cocktails that, for different purposes, and so you know if people are remembering, oh when I had my colonoscopy it wasn't like that, I don't know if it's quite the same.

S: That's like conscious sedation.

C: Yeah, that's what I thought it's not like the the hardcore stuff. Like, I had a sore throat for two days.

S: They intubated you.

B: Yeah.

C: Yeah, well, luckily they didn't do full intubation, they did this secondary thing that just like it's supra-epiglottis instead of going through your epiglottis but it still carves up your throat. Yeah, I was like oh god. Yeah, so, fun times.

S: I'm glad you're doing well.

C: Thanks.

S: that it turned out alright.

E: You sound great.

Shameless Promotion (3:30)

Upcoming Shows

S: So, we don't often do this, so I have no shame about doing this whatsoever (Cara laughs). We're going to do a segment of a couple of things of shameless promotion. Before we get to the news items. The first thing is that we have some shows coming up. Jay, you want to talk about them?

J: Yeah we have a lot of stuff coming up Steve. So, we will be in Arizona on July 15th and 16th. On both of those dates we'll be doing an extravaganza. On the 15th we'll be doing an extravaganza in Phoenix and on the 16th we'll be doing extravaganza in Tucson. We also have two private shows one in Phoenix and one in Tucson. Those dates and times literally by the time you hear this they'll probably be on the website, so go take a look and if not, they'll be there very very soon. You can go to theskepticsguide.org/events to see all this information.

S: Now for the private shows we're doing something a little bit different, so I wanna mention that. Normally we do you record a two hour show, right, and there's a little bit of chit chat around it but basically you're you're you're seeing us record a full two-hour show, episode of the show. But now we're going to be we're starting to do an enhanced private show or private show plus, we're still branding it. (laughter) But it's something like that, where it's going to be three hours, it's gonna be not two hours but three hours. We'll be still be doing a live show in the middle of it, but we're gonna be doing other things just for the live audience, there's gonna be a lot more interaction, we're gonna be experimenting with different games and other events. And, you know, George might do some music or whatever, it's going to be an expanded event with a lot more you know interactive stuff going on and interaction hanging out with us. So, we're going to see how that goes, so yeah, so keep an eye out for that. And don't forget for the extravaganzas we also have VIP tickets where you get to spend an hour with us either before or after the show depending on the schedule of the venue. You get extra swag, you get, you know to to take pictures with us and stuff like that. So if you're not going to the private shows and you you want some VIP time, that is an option for the extra, for the extravaganzas as well.

C: Oh and you get the best seats in the house.

S: And you get the best seats.

C: Yeah.

E: Yep.

Second Book Launch

S: All right and so here's the other, the other half of our shameless self promotion is the our second book just launched. So, not published but it's publishing September 27th but you can now pre-order it. this is The Skeptics’ Guide to the Future

J: Whoa, that's such a cool title Steve.

S: It is. (laughter) Bob, Jay and I are the authors on this one. We had so much fun writing this book─

B: Oh my god.

S: ─and we learned an incredible amount. Ss much as we felt like oh we're steeped in all of these topics, just doing the research for the book, well, it just takes you to the next level.

B: Right, exactly.

S: I actually changed my mind─

B: There's a new layer on that onion.

S: ─I changed my mind on some of these technologies based upon the research that we did.

B: Sure.

S: It was really profound. So, a lot of fun, I think the book came out very very well. You can, we'll have the link on the show notes, we'll have the link on the SGU site, it's grandcentralpublishing.com and look just look for the Skeptic's Guide to the Future and you can pre-order it, you can pre-order pretty much everywhere both the hard copy, the kindle version and the audio book. So there will be an audio book, I'll be recording that over the summer. So all of those can be pre-ordered. We really, if you feel like you know you might be buying this book, we really encourage you to pre-order it because that helps us get over that threshold to maybe get on a best seller list. Which of course would really help promote the book. So we would definitely appreciate it if you, if you pre-order your copy, that will help us a lot. And I think the cover is totally awesome.

B: Oh my god I love it, my new background on my phone.

J: Steve I was going to get that tattooed to my face, you think that's going too far or what?

E: Not far enough.

B: Just do one cheek, one cheek.

S: Back? Lower back?

J: The lower back?

S: Or maybe a scapula, I would do a scapula. Yeah, so check that out, we're really excited about that.

J: Steve, now, don't forget, there is one more thing NECSS 2022. It's a lock everybody, remember, I think I said last week or this could have been on our live stream, I said we weren't 100% sure. Now I'm 100% sure. We are definitely doing NECSS 2022. It will be the first weekend of August, that's August 5th and August 6th and we have a keynote. Not a keynote speaker, a keynote situation. (laughter) You ready to hear this? The keynote situation is that Bill Nye will be having a discussion with David Copperfield.

B: Oh.

C: That's right copper. Oh my gosh I'm so excited.

S: Good try, good try Cara.

J: We interviewed, I know, you keep working on that accent.

C: No no, I intentionally didn't do that's right copper, because this this needed something louder and more exciting.

J: You guys might remember we interviewed David six months ago, middle of the summer I think it was. It's hard, it's hard to tell, the pandemic has destroyed my ability to tell time.

E: It was last fall.

J: And we had a great time talking to him. He was a ton of fun to talk to.

B: He was great.

J: He has you know an endless number of stories because he's been doing something amazing for so long that he literally like we had to like stop the interview because we didn't have any more time. But we loved talking to him and that was the impetus for asking him to speak at NECSS and he, you know, he very generously said that he would be happy to do it. And you know Bill is now involved with NECSS formally and Bill is going to talk to him. So the two of those guys are going to have a really fun conversation. That's our keynote. It's a, it's a keynote situation that we would like you to enjoy. So you can go to necss.org, n-e-c-s-s dot o-r-g for all the details that you need to sign up. Now keep in mind we're filling in our speaker list as we go. And we have a theme this year and the theme is navigating the misinformation apocalypse. So we will be we will be hitting some themes here during the conference about how how do science communicators deal with misinformation. How should the general public deal with misinformation. How do we deal with it? Because it's everywhere, coming from all directions and that's what we hope to answer during this conference, so please join us.

B: We are doomed.

S: And did you mention that it's an all digital conference?

J: Steve, did you know that NECSS 2022 is all digital? It's live streaming? You can watch this conference literally from anywhere you want in the world.

S: In your underwear.

J: Right. You know, you could be eating cereal as you're watching it. The cool thing is is, you could get your ticket and then you could watch the conference for up to like six months, because it's just there online whenever you want, you can watch it live, if you can't make it you don't have to watch it live, you can watch it basically whenever you want. But if you want to see it live with us, it'll be on August 5th and 6th of this year.

S: All right thanks Jay.

News Items

Redefining the Second (10:27)

S: All right guys let's move on to some news items. And Jay you're gonna start with redefining the second. So this is another series of news items about measurements and stuff, whenever there's a significant update to measurements we like to talk about it. this one this time it's the second.

J: This one has a really cool history to it, there's so much more here than I could cover. Look, scientists are about to do something big, to something very small, right? Seconds, right they're small Cara, but they're important. The second is important. So they're gonna change the definition of the second. And I don't mean like we're going to call it something else. They are refining the accuracy of the second and let me tell you the story behind it. Now historically people would track time by the Earth's movement. This is what people have been doing for thousands of years. The Sun's relative position would change in the sky, right? And since the Earth's rotate rotation is slowing, which it factually is, scientists knew that they had to measure time in a way that was considered to be a 100% constant, right? Because the Earth, the Earth's rotation is slowly, slowly slowing down, that means that the amount of time it takes the Earth to rotate is changing. And that's not good when you're tracking seconds and when seconds or even hundreds of seconds or thousands of seconds are important to do scientific measurements. So for example Earth, Earth's slowing rotation lost three hours of time in the past two thousand years. Now I get that that might not seem like a lot but, but to science it's intolerable! Like, right, scientists can't stand that it's not, it's not a predictable measure of time because you know one second is changing if you, if you use that, if you're measuring it via the rotation of the Earth. So, I recommend that you read some history of the way that humans have been tracking time and how time tracking came to be because it's fascinating. But to give you a tiny little bit of information, before 1967 the second was considered one over eighty six thousand four hundredth of a day. That was, that's that was basically what you needed to know. And all this led scientists back in '67 to change how we measure time by looking, now instead of saying we're going to use the Earth or astronomical ways of defining how long a second is, we are going to use atoms, right? Like an atomic clock, I'm sure you've heard of the term atomic clock. Well what the hell does that mean? What is an atomic clock? Scientists needed something back then that was predictable and more constant than the rotation of the Earth. So they used the motion of atomic particles, because they never wear out, right, you know atoms don't wear out. And they never change their properties. Atoms are going to behave the way that they are at the speed that they're going to behave under normal conditions and that's it forever. Until the universe ends so from a scientific point of view, they are the perfect way to measure time. Using atoms and using the movement of atomic particles. So they ended up using, they ended up using something called cesium which you know it's it's an atom.

C: It's an element.

J: It's an element.

C: It's weird to say it's an atom.

J: Yeah, you're right, it's an element made of atoms. Okay. So because that, because cesium, they have a heavier atomic weight and it's its resonance frequency was easier to study and track. They use microwaves to excite the cesium atoms to emit a flash of light at regular intervals and those regular intervals were the movement of the atom itself. They had instruments that could pick up the flash of photons and measure time using these regular flashes that that came from the atom when they hit them with microwaves, right?

B: Right so like 9.2, 9.2 billion flashes in a second.

S: Yeah.

B: So that number is very precise.

C: How do you count something like, how do you have the resolution that counts something like that? (laughter)

S: Okay, I think, I think I can give a more technical explanation than that. It's tricky and it's hard to find sources that really give it a good description, but here we go. Cesium-133 atoms essentially exist in two energy states, let's just say a low energy and a high energy state. So they use a magnet to separate the two, so that you have a pure stream of low energy state cesium atoms. They then expose it to microwaves at precisely the right frequency, that 9.2 billion cycles per second which bumps the low energy cesium items into a high energy state. They then use another magnet to remove any remaining low energy cesium atoms and they count the high energy cesium atoms. Which then feeds back into the microwave generator so they can fine-tune the microwaves to the precise frequency that maximizes the number of high-energy cesium atoms hitting the detector, right ? So that's how they make that that frequency extremely, extremely precise. Here's where it gets a little tricky and it's hard to find an exact description. I think there's different types of clocks that may use different methods but a common method at this point is then to use a quartz crystal, like a regular quartz time keeper. And they use the resident frequency of the microwaves to fine-tune the oscillations of the quartz crystal. In one description where they get they make it 10 million cycles per second. And then you can just use regular electronics to measure those 10 million cycles per second. Basically every 10 million cycles it spits out a pulse, that's one second. So but I know there's a, there's a Fountain Cesium Clock at NIST which is uses a slightly different method. It gets a little technically complicated at that point but it's essentially they're fine tuning the resonance frequency of the microwaves to the cesium atoms by measuring how many of those atoms get bumped into the higher energy state and then they have to feed that back into some kind of counter which could in one type uses just a regular quartz crystal to measure time.

J: All right so guys the International Bureau of Weights and Measures which I think is pretty cool. They ended up facilitating the official change in measuring the second using these cesium atoms back in '67. But keep in mind that astronomical time and atomic time still needed to be synced up since we're living on Earth and we need to we need our, you know, our day and night and our 24 hour cycle to still make sense, even though it's a little bit longer than 24 hours, they still had to sync them up. So what scientists did is they add a leap second to the atomic time roughly every year and a half. And this accounts for Earth's slowing spin.

C: And this is why like our GPS's work?

J: Yeah right.

S: Part of it.

J: If they didn't if they didn't sync things up like this lots of stuff wouldn't work, right? So they have to they have to sync it up because we are bound to the Earth and we live on the Earth so therefore we need our astronomical time keeping and our atomic time keeping to jive with each other so we have these fix it, fix it little doodads that we do every year and a half or so. So updating the measure of a second is happening because scientists have created new and very sensitive instruments called optical atomic clocks. these work like the cesium time tracking method but the new version can detect much faster atomic movement. So they can, they can use many different atoms today or ions with the latest equipment that they've come up with like like strontium and mercury and aluminum, to list a few. Now none of them have been picked as the new default atom or ion because all of the this is still in the laboratory, it's not ready for prime time yet, you know, they haven't dialed everything in yet. The equipment takes many people to operate, you know, it's not, it's not simple enough or elegant enough to use as the new standard yet. The equipment takes many people to operate and is simply not elegant enough to use as the new standard yet. The equipment needs to be perfectly stable as an example it has to be shielded from the Earth's magnetic field, you know, they need to chill the atoms or ions to near absolute zero. This slows them down and then they shoot lasers at them. And they're searching for the best wavelength of light that works best with each different atom or ion, right, because they want they want that really specific wavelength of light that's going to make the atom do something, like give a predictable reaction. Like it might create photons or you know it might you know give off a certain amount of energy at some at some point that they can detect.

S: Yeah so essentially they're using atoms that have a resonance frequency in the optical range rather than the microwave range. So they're, that resonant frequency is about 50 000 times greater than for cesium atoms and therefore they're 50 000 times more precise.

J: A second type of laser called a Femtosecond-Laser Frequency Comb

B: Oh baby.

J: This is what Bob uses in the morning to comb his hair. A Femtosecond-Laser Frequency Comb. This laser is used to read the wavelengths of laser light that excites the atoms or ions. So this process can detect and measure these pulses of light a hundred thousand times faster than the cesium clocks from 50 years ago.

E: Whoa, that's, that's significant.

B: Nice.

J: Right? So that right there is how much more accurate the clocks, you know, the atomic clocks are today than the ones that they created back in '67 or earlier. This means that these new methods of measuring time are are just much more accurate and much more in line with scientific precision. Which is what we want here. So, after all this I would expect at least Cara or Evan to say, hey why do we need the second to be so much more precise? Who cares?

C: For our GPS's

E: Hey, why do we need the second to be so much more precise?

J: Thank you Evan, I'm really glad that you're absorbing this. One reason is that time is affected by gravity.

E: Is it?

J: And you might go okay so what. Well time moves slower when you are near a planet or a black hole, right? So the closer you are to a gravity well, anything that is producing gravity, could be a planet, could be a Sun, could be a black hole. Time is not constant in our universe because of this. Time is constant to the, you know, to your relative position but time is moving faster and slower all over the place in our universe because of gravity. Because atomic clocks are affected by gravity and their time tracking will reflect this, this means that they can detect things like gravitational waves or dark matter. Think about that. Right? Because they are, they're so sensitive to changes in gravity, these these new atomic clocks. They can detect gravitational waves, that is freaking amazing. This was proven back in─

C: Would they be used for that purpose?

J: I absolutely think so Cara, I mean I think that they're so sensitive

B: Wait a second, wait how did that work?

J: I'm gonna tell you right now Bob, I'm gonna tell you right now, check this out, this was proven back in 2015. So physicists at NIST were working on these optical atomic clocks and they noticed that the time was not consistent on all their clocks that that were situated around boulder Colorado. They have multiple, multiple versions of these clocks that they're, that they're working on and that they're testing and they were very close to each other all, you know, all in the same city. But the time that they were representing was off and they're like what's going on, what the hell is this? So it turns out that all the clocks were at slightly different altitudes.

B: Yes! Right.

E: The altitude matters?

J: So why does that matter? A clock that was one centimeter higher than another one, that was a few miles away was reading time differently because it was farther from the center of the Earth which means that it was farther from the center of the gravity well that it was pulling on it. One centimeter guys. And they, and these these clocks recorded the difference.

B: All right, so...

J: One centimeter in altitude, Bob, think about that.

B: I already have, I talked about it like a year and a half ago on this show.

J: What did you think, what was your reaction?

B: You said gravitational waves Jay.

J: Yes. They said, Bob, the article said that these things could detect gravitational waves and dark matter.

S: Bob, Bob, I think this is what jay's talking about. So I'm seeing a study from 2015 "Using Atomic Clocks to Detect Gravitational Waves" they say that if we they, they're pointing out theoretically, that if you had an array of atomic clocks distributed along the Earth's orbit around the Sun, that that would have the sensitivity to detect the time dilation effect of a megahertz gravitational wave. Such as those emitted by supermassive black holes and binary. So you would have to set up an instrument using these clocks to detect it.

C: Yeah.

S: You're detecting the difference you know between an array of these atomic clocks but they are sensitive enough that they can detect something of the magnitude, the relativity effect of the magnitude of a gravitational wave.

B: So I'm just trying to think how, how it stretched space time by like, by like a thousandth of the diameter of a proton, how that is going to affect an atomic clock.

S: The simultaneous measurement of clock rates at different phases of a passing gravitational wave provides an attractive alternative to the interferometric detection of temporal variations in distance.

C: Yeah it sounds like it's not the clock itself, it's the clock relative to the clock next to it.

B: Yeah yeah, so yeah, oh yeah of course, of course, but okay all right, I get, I get that. But I mean, that just just that just came out of left field for me.

J: They're saying that it's possible that they will have like have finalized this way of measuring time, probably by the second half of this decade. You know, They're, I don't think they're in a big rush. I think they want to wait until they nail it.of course.

S: Yeah they have time. (laughter)

J: But. But we will be someday very soon, we will be measuring, we will be measuring the second now with more precision, you know, once that they master this technique. So nothing has changed other than the fact that it's more accurate and that it can do a lot of cool things that piss Bob off.

S: Okay all right thanks Jay.

C: Love you guys.

B: Love you Jay.

NFT Medicine (24:24)

LHC Restart (42:29)

Energy Psychology (52:16)

Researching the Paranormal (1:03:41)

Who's That Noisy? (1:14:30)

Answer to previous Noisy:
old-fashioned jaguar call, made with large plastic tub and leather lace


New Noisy (1:20:39)

[bird-like siren sounds and whoops]

J: ... If you think you know what you heard this week or you heard something cool because you're a cool person and you're in cool places and you do cool things, send me a cool Noisy at wtn@theskepticsguide.org.

Questions/Emails/Corrections/Follow-ups (1:21:18)

_consider_using_block_quotes_for_emails_read_aloud_in_this_segment_
with_reduced_spacing_for_long_chunks –

Correction #1: Native vs. Endemic

Science or Fiction (1:28:43)

Theme: Future Technology

Item #1: Using a quantum 2D material, scientists have produced the highest temperature ambient pressure superconductor, at 250 K (-23° C).[6]
Item #2: NASA Scientists have developed a metal alloy that has twice the tensile strength, three times the ductility, and at least 1000 times the durability at high temperature and stress as existing superalloys.[7]
Item #3: Using machine learning and genetic modification, scientists have created a bacteria-produced enzyme that can rapidly break down PET plastic (which makes up 12% of global solid waste) so that it can be reused, and is practical for industrial scale use.[8]

Answer Item
Fiction Ambient pressure superconductor
Science Scalable plastic-eating enzyme
Science
Nasa metal alloy
Host Result
Steve sweep
Rogue Guess
Cara
Nasa metal alloy
Evan
Nasa metal alloy
Jay
Nasa metal alloy
Bob
Nasa metal alloy

Voice-over: It's time for Science or Fiction.

Cara's Response

Evan's Response

Jay's Response

Bob's Response

Steve Explains Item #3

Steve Explains Item #2

Steve Explains Item #1

Skeptical Quote of the Week (1:55:15)

There is an urgent need today for the citizens of a democracy to think well. It is not enough to have freedom of the Press and parliamentary institutions. Our difficulties are due partly to our own stupidity, partly to the exploitation of that stupidity, and partly to our own prejudices and personal desires.
Lizzie Susan Stebbing (1885-1943), British philosopher, from her 1939 book, Thinking to Some Purpose

Signoff/Announcements (1:58:53)

S: —and until next week, this is your Skeptics' Guide to the Universe.

S: Skeptics' Guide to the Universe is produced by SGU Productions, dedicated to promoting science and critical thinking. For more information, visit us at theskepticsguide.org. Send your questions to info@theskepticsguide.org. And, if you would like to support the show and all the work that we do, go to patreon.com/SkepticsGuide and consider becoming a patron and becoming part of the SGU community. Our listeners and supporters are what make SGU possible.

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Today I Learned

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