The 2018 physics Nobel was not awarded for the creation of femtosecond pulses. That effort was awarded in 1999 to Ahmed Zewail. The 2018 prize was for optical tweezers and chirped pulse amplification, which make use of femtosecond pulses that were in widespread use by then.
I don't get it. Wouldn't sending a single photon be the shortest possible light burst? Wouldn't the shortest possible light pulse be a two-photon release at gamma-ray frequencies? I'm sure the answer is no because I'm a layman hack but those are the questions that come to mind.
You can absolutely produce a single photon but that isn't that useful for imaging but does have a lot of other uses. In this case they can have a lot of photons that are all arriving at the same time.
A single "photon" is a wave, not a particle (wave of probability) and the Heisenberg uncertainty principal is fully in effect and results are random. You only can image things when you have deterministic results, collapsing the waveform of both the electron and the photon. Note that this does change state - it isn't passive.
There are a lot of questions about the reproducibility and/or interpretations of a lot of capitalist-influenced science. Light seems to be a major one. Every "single photon" emitter I've read about, it turns out, sends "packets" of photons, but they call them single photon emitters, I think, because it fits the narrative of the physics' status quo, aka Dr. Whitten. My spelling might be off, but he's the author of M "Theory." He's why string "theory" (hypothesis, not theory) became so prevalent and string hypothesists got into the upper echelons across physics departments nationwide. He also pushes for the big bang, ignoring gravity's effect on red shifting to make it look like the universe is expanding. I'm not saying it's not, but the behavior of popsci-influencers and the news around the topic is sus, and I *am* saying that a lot of scientists have ignored the scientific method and any variables that work against the narrative of their benefactors or their own preconcieved notions, i.e. "the chemical imballance theory" of depression, everything to do with anticholinergics, lead industry funded studies of lead's toxicity, and when scientists told us that cigarettes are good for you.
Well deserved Nobel Prize. I applaud you for an excellent explanation and for your advocating for Fundamental research, intellectual justification not potencial profit motivation. PS new subscriber.
Could you imagine how much ridiculously fast data storage is going to be required to film something as fast as an electron? Do we have the data speeds available to do it? I'm excited to see how many new discoveries this will lead too. On the other side of that coin. The brute force method of breaking encryptions might become a viable option soon. We're going to need some much bigger prime numbers
Bravo! Well done ... you've increased the awareness of attosecond technology, well below a trillion-fold, but you added to my knowledge of this incredible advance in the science of electron motion. It's certain to have myriad applications to future development in all fields.
Well, I hope it helps in advancing the science to such a degree, that people stop perceiving an electron's movement as if it's some sort schrodinger's cat, simply because of ya don't have a good enough camera.
I can understand why attosecond light pulses would be needed to detect electrons. In a physics lecture I saw the professor said in the time it took to blink his eye, the molecules in his eye vibrated 10 billion times and for each molecular vibration the electrons oribted the nucleus a million times. So electrons are moving pretty fast, necessitating fast detection methods.
I literally teared up when Anne was applauded by her class. But particularly because I was overcome with how insanely short the light pulse is and the thought of what looking at electron motion will mean for science! Great video! Thanks so much for sharing
Attosecond or 10^-18 second is one step closer to a minimal bit of time, defined by Planck as 5.391X10^-44 second. It means we approached one step closer to the fundamental understanding how Universe works.
Thanks for the informative video. It's always great to hear about these breakthroughs which revolutionize physics and eventually end up heing part of our daily lives. This probably compares to the invention of the laser itself, the electron microscope (so we can see all those funny bug pictures :-), and the transistor and then the integrated circuit so we can watch videos like this on our phones. Thanks again, and you have a new subscriber. Cheers from Canada :-)
So some of the best supercomputers today do roughly 10^18 calculations per second. One second is comprised of 10^18 attoseconds. If we can compute with light pulses, which we can, than adopting what this man figured out would make modern supercomputers look like what the Eniac looks like to us today. Truly amazing.
Nah, in the Corporate states we gotta worship cons like Musk and Bankrupt-Fried and Bloody Holmes and Bezos and millionaire who plays a billionaire on TV O'Leary, etc. etc. They're billionaires you know.... until they're not and their frauds fall apart of course.
Imaging how electrons move *in* a molecule? can we do this without disrupting the system too much/making the electrons fly off, like in the heisenberg microscope thought experiment?
The measurement is still limited by the Heisenberg uncertainty principle. So with the extra spatial information come at the cost of less momentum information
To bad for those so called noble prize Winners.... hahahaha .... they did not present any registration of electrons observed. Only words and graphical simulations... plus you can’t pretend or insinuate to have violated the Heinsberg principle of indeterminacy with zero empirical material evidence. Any scientist must wonder what the hell is the motivation behind this prize.
These are excellent questions and I would like the answers. I have another question. how does these atosecond pulses compare to the plank length, the shortest length?
how is short pulses different than just using lasers with shorter wavelength? and if one attosecond is the duration of one pulse, what about the time between pulses?
@@ScienceDiscussedhmm... i was thinking about that camera frame analogy. even if a pulse was very short, if it took much longer between pulses we wouldn't really get that many frames...
4:28 The stock footage is of the lens' *aperture* , not the shutter. These cameras have focal plane shutters, which _could_ be shown if you take off the lens, and I'm sure there is stock footage of it. You might have confused the aperture footage with that of a *leaf shutter* in action, which would also illustrate your point.
Wouldn't Heisenberg's uncertainty principle prohibit knowing where the electron is at the scale of atoms? My physics classes are way behind me, but I remember the strange shapes of electron orbitals around hydrogen, like spheres, donut, and hourglass shaped, they were just volumes of higher probability. We were told that an electron is just a three dimensional stationary wave.
the reduced planck constant is around 10^-34 Js, diameter of an atom is around 10^-9 meters, so you can still get very precise information about position and momentum at least theoretically, although I don’t know anything about the field so take that with a grain of salt ofc.
Prof. Strickland's Nobel Prize was for chirped pulse amplification, not for creating femtosecond pulses -- to clarify, short laser pulses were already a thing (though I'm not totally clear whether femtosecond laser pulses were achievable yet), but were limited in their potential because you couldn't increase the power without damaging your gain crystal or lengthening the pulse due to nonlinear effects. The CPA allowed you to take low-energy very short (for the time) pulses, and amplify them by orders of magnitude, enabling all kinds of new applications. I think they demonstrated this on picosecond pulses in the 1985 paper. Also, can we all stop saying "fast" pulses? It's light. The light coming out of these lasers travels at the same as the speed of light coming out of your computer screen right now. What makes this light so interesting is that it's very, erm... brief; unlike this rant.
@2:23 wait, why do all of these women have uncannily-similar shaped heads? Guys... I think I have some bad news: the Swedes are picking female Physics Nobel Laureates ON THE BASIS OF PHRENOLOGY! (but in all seriousness, Anne L'Huillier is awesome! I adore her for still teaching, she clearly loves what she does 🤗)
How do you know you have light imulses lasting only attoseconds? Don't you need a detector (like a photomultiplier tube) and amplifier with bandwidth (or rise and fall times) even faster than the signal they look at to know the shape/width of your light pulse? I know oscilloscopes can have GigaHz bandwidth, but I'm not aware of detectors that are that fast.
man i've watched videos and read the same wikipedia article you did and still dont understand why you need light pulses shot out of a laser at 10^-18seconds. Dont you need a detector that can operate at that frequency? Are you saying that there is a detector which can operate at 10^-18 or 10^-19seconds that can also instantly switch on and off to record an impact from this laser pulse? What would you gain shining this light at something like water? how fast of a detector would you need to catch light standing still in a vacuum?
To bad for those so called noble prize Winners.... hahahaha .... they did not present any registration of electrons observed. Only words and graphical simulations... plus you can’t pretend or insinuate to have violated the Heinsberg principle of indeterminacy with zero empirical material evidence. Any scientist must wonder what the hell is the motivation behind this prize.
It is a great question. I didn't look into what type of detectors they are using. But no detector will be able to be reset in that timeframe. So I would imagine that they send a pulse of light, detect it, reset the detector, and then send the next pulse of light.
@@ScienceDiscussed I am working in this field and we are normally doing the so-called pump-probe experiments. We send the attosecond pulses together with delayed infrared pulses (most often we just split the IR pulse before harmonic generation and take a small fraction of it to act as a probe) into matter and look at and detect the electrons ejected through a photoelectric effect. Then we vary the delay between the attosecond and IR fields very precisely, which in turn affects the properties of the ejected electrons. These electrons can convey a lot of information about the pulses themselves or the system that we study. (People often call it "taking a series of snapshots at different delays and thus making an electron movie".
does the width of the pulse related to the median frequency? is it easier to make short pulses if the highest intensity component in the pulse already has super high frequency?
How did they even measure that the pulses are that short? Or did they just compute the result from fourier frequencies ? How do we know that it even holds true in those conditions ?
1:17 Am I missing something? For this illustration to be correct, the universe would have to be 31.7 billion years old. I wouldn't normally let something like this bother me but it was created by the Royal Swedish Academy of Sciences...
But a pulse of what exactly? the pulse is shorter than the wavelength of the photons as far as I have gathered. Nobody has implied that these are X-ray or gamma pulses and visible/UV frequency waves are on the order of femtosecond.(which was why the theory was that femto was the fastest)
I wish you could explain what an electron does in an attosecond right at the beginning of the video. After 3 minutes, I still don't know the answer or why this is worth a Nobel prize.
is no one gonna talk about the potential that this discovery could lead to breaking the uncertainty principle that dictates an electron can only have either their position or their velocity known at any given moment, but never both simultaneously?
Unfortunately that’s not what’s on the table concerning this breakthrough, that is fundamentally not possible, the more you try to prob for information the further nature will sensor information about it, that’s why quantum makes everyone’s lives harder. You can’t really break the uncertainty principle, you can only get closer so to speak, a zenos paradox
Yes it deserves a Nobel Prize in Physics! Finaly a Nobel Prize in Physics that is worthwhile, not another String Theory or Particle Physics ! No Theory Should receive a Nobel without Cocrete Prof by Measurement, Until they are proven by measurement they are just Conjecture! People can dream up Theories faster than the hard work of developing measrement Techniques!
If we can measure the position of an electron, we cannot know its charge, its direction of travel, or whether it has "spin". Did we reach a new threshold in Quantum Physics/Mechanics/Chromo-dynamics? Can we now count or measure what happens to Leptons Bosons and Quarks.
Why is it significant that another woman won in the hard sciences? Sex differences are real, and the ratio of men to women at genius level intelligence is quite high, so we would expect relatively few women to have achieved this. This obsession with giving concessions to women despite real differences in traits is causing material harm with women already becoming the majority of students in university and the majority in very socially relevant fields like political science, law, and medicine.
Seems like there will eventually be faster light pulse. What technical challenge is preventing that from happening now? What is next speed to look for that will unlock some profound area of study?
Amazing, I think there was a single sentence of explanation of the technique, lots of sentences about the sex of the prize winner, lots of sentences fantasizing about the possible outcomes using the technique, but 1 sentence explaining the technique.
I wonder what the technological limit to measurement is? Similar to how the plank scale is the limit to probing nature for further information, what would be the equivalent to that for cameras/frame rates?
Whenever photons interact with an electron, it transfers some energy to it which makes it difficult to study the electron in atomic and molecular levels. How does this discovery solve that problem?
Light moves the length of an atom, roughly, in an attosecond. I hate scientists who say, "This is barely comprehensible", then explaining the thing in the most convoluted manner, by referencing the vibrational movement of electrons, which are actually sub attosecond in size..
@@user-zu1ix3yq2wtime is relative indeed but the concept is still relatively simple. The age of the universe is determined primarily through observations and calculations based on our understanding of cosmology. Here's a simplified overview of the process: Astronomers use the Hubble constant (H0), which represents the rate of the universe's expansion. By measuring the redshifts of distant galaxies and their recession velocities, they can calculate H0. With the measured value of the Hubble constant and the assumptions of the universe's composition (e.g., matter, dark matter, dark energy), scientists can estimate the time it took for the universe to expand to its current state.
@@user-zu1ix3yq2wtime is relative to speed. Time from the outside perspective is always the same rate. It's just when you tavel at speeds weird shit happens.
Not a physicist, but would this allow us to image the exact position of an electron so frequently that we would be able to calculate both its position AND speed?
I believe so, or at least allow us to look at electron-electron interaction of different atoms that make up a molecule. Lots of new discoveries to be made!
I never understood how you can have a pulse significantly shorter than it’s wavelength. How can you even determine the frequency? Wouldn’t their be quantum effects of uncertainty interacting with it? This shows my lack of deep understanding in optics😅
The Heisenberg uncertainty principal is still fully in effect for the electrons, and they are in states of superposition. Imaging them is interfering and collapsing the waveform.
@@amihart9269 You're talking nonsense and really out of your depth. Superposition is very real and has 150 years of experimental support. If it weren't real you wouldn't have quantum computers or teleportation, which are practical uses. Wave function collapse is part of the standard model and copenhagen interpretation compromise which is the basis for the standard model. There's alternatives like pilot wave theory and Everett's many worlds interpretation but they are all probably mostly correct and that's generally acknowledge.
These days, there are the vast majority of scientists who run theoretical computer simulations rather than actual practical experimentation on matter. And that's why science has grounded to a halt for the last 60 yrs.
No lol we already have fiber optic which is absurdly fast and expensive, this would be even more expensive to get running, and for what benefit? It might be used in some industries for short distance but necessary information travel but you and I arent seeing noble gas lasers in our modems anytime lmao
