Highlights from the first 50 years at the historic Fermi National Accelerator Laboratory.
Zz.
Tuesday, January 31, 2017
Monday, January 30, 2017
Presidential Executive Order and US Conferences
With the two big conferences looming this year, the APS March and April Meetings, it will be interesting to hear how the recent presidential executive order banning entry by visitors from 7 predominantly-Muslim countries will have affect. Citizens from countries such as Iran already had a long and arduous process in gaining a visitor visa to come to the US, so much so that many won't even bother to try.
So now, with the entry ban, looks like this will have an impact on visiting scientists from these affected countries. Unfortunately, this will create an even bigger ramification, because international organizations will be less inclined to hold major conferences in the US where some of its members will not be allowed to attend. This should have both scientific and economic impacts.
So far, there has been no official word from the APS on this matter.
Zz.
So now, with the entry ban, looks like this will have an impact on visiting scientists from these affected countries. Unfortunately, this will create an even bigger ramification, because international organizations will be less inclined to hold major conferences in the US where some of its members will not be allowed to attend. This should have both scientific and economic impacts.
So far, there has been no official word from the APS on this matter.
Zz.
Friday, January 27, 2017
3 Things Everyone Should Know About Physics
This is an exceptionally good answer to the question: "What do physicists wish the average person knew about physics?" The answer was written by Inna Vishik, Assistant Professor of Physics at the University of California, Davis.
Zz.
- Physics makes predictive models about the natural world based on empirical observations (experiments), mathematics, and numerical simulations. These models are called ‘theories’, but this does not mean they are speculative; physics theories explain past behavior and predict future behavior. When a previously-validated theory fails to explain the behavior in a new physical system, it doesn’t mean the theory is suddenly ‘wrong’ altogether, it means that it is inapplicable in a certain regime. It is very exciting for physicists when these exceptions are found, and it is in these holes in our models that we propel our understanding of the physical world forward.
- The domain of physics is vast. Some physicists study the existing universe around us. Some study the smallest constituent particles and forces of matter in this universe. Some manipulate clusters of atoms, and some manipulate light. Some study crystalline solids and the myriad properties they can have when quadrillions of atoms and electrons are arranged in slightly different ways. Others study biological systems. This is not a full list of the many subfields in physics, but what they all have in common is they combine classical (including continuum) mechanics, quantum mechanics, statistical mechanics, general relativity, and electricity and magnetism in various configurations to explain the physical and engineered world around us.
- Research in physics and other fundamental sciences play three crucial roles in an advanced society; they cement our cultural legacy by exploring one aspect of the human condition (the universe we occupy), similar to the role of the arts; they educate a portion of the work force in solving difficult, open ended problems beyond the limits of prior human innovation; they provide the seeds for future technological developments, which is often realized decades in the future in an unpredictable manner (i.e. not amenable to quarterly earnings reports). At the time of their inception, electromagnetic waves (late 19th century), quantum mechanics (early 20th century) and lasers (mid 20th century) were viewed even by their progenitors as esoteric curiosities; now they permeate our life, technology, and medicine so deeply that no one would question their practical importance. In the modern physics research era, there are newer ideas that might have an equally important impact 50 years from now, but they will never be realized without continued investment in the public good known as fundamental science.
Zz.
Metallic Hydrogen?
The big news so far this week is the publication on the possible (key word) creation of solid metallic hydrogen.
If this is true, then this is a significant discovery and confirmation of a prediction from many years ago. Understandably, with the press releases on this work, the popular media have been going ga-ga over this.
https://phys.org/news/2017-01-metallic-hydrogen-theory-reality.html
https://www.yahoo.com/news/u-scientists-create-metallic-hydrogen-possible-superconductor-ending-043206674.html
http://www.businessinsider.com/metallic-hydrogen-created-2017-1
However, upon trolling all the various news reports, only the Independent so far has an update on the news story about doubts about this discovery.
http://www.independent.co.uk/news/science/hydrogen-metal-revolution-technology-space-rockets-superconductor-harvard-university-a7548221.html
This is taken from a news report published in Nature:
http://www.nature.com/news/physicists-doubt-bold-report-of-metallic-hydrogen-1.21379
As with ANYTHING in Science, we have to give this a period of gestation before we all jump onto the bandwagon. It needs to be independently verified, and even the authors admit that this needs to be refined even more to produce a conclusive evidence of metallic hydrogen.
Zz.
If this is true, then this is a significant discovery and confirmation of a prediction from many years ago. Understandably, with the press releases on this work, the popular media have been going ga-ga over this.
https://phys.org/news/2017-01-metallic-hydrogen-theory-reality.html
https://www.yahoo.com/news/u-scientists-create-metallic-hydrogen-possible-superconductor-ending-043206674.html
http://www.businessinsider.com/metallic-hydrogen-created-2017-1
However, upon trolling all the various news reports, only the Independent so far has an update on the news story about doubts about this discovery.
http://www.independent.co.uk/news/science/hydrogen-metal-revolution-technology-space-rockets-superconductor-harvard-university-a7548221.html
This is taken from a news report published in Nature:
http://www.nature.com/news/physicists-doubt-bold-report-of-metallic-hydrogen-1.21379
As with ANYTHING in Science, we have to give this a period of gestation before we all jump onto the bandwagon. It needs to be independently verified, and even the authors admit that this needs to be refined even more to produce a conclusive evidence of metallic hydrogen.
Zz.
Wednesday, January 25, 2017
The Technology Of Detecting Gravitational Wave
The biggest physics news of 2016 was certainly the detection (finally!) of gravitational wave by LIGO.
In this CERN Courier article, the physics and methodology of making such a difficult detection is described. As you read this article, keep in mind that at each step of the development and evolution of the facility, there had to be advances and improvements in the detection method, which by itself, is significant. The technology and engineering involved in many this detection, and in many other science experiments, often drives the development of the technology that eventually finds applications in the rest of the population.
Zz.
In this CERN Courier article, the physics and methodology of making such a difficult detection is described. As you read this article, keep in mind that at each step of the development and evolution of the facility, there had to be advances and improvements in the detection method, which by itself, is significant. The technology and engineering involved in many this detection, and in many other science experiments, often drives the development of the technology that eventually finds applications in the rest of the population.
Zz.
Labels:
Experiment,
General Public and Science,
Gravity,
Relativity,
Technology
Thursday, January 19, 2017
Rick Perry Backtracks On DOE
During his confirmation hearing today, Rick Perry changed his mind about wanting to shut down the US Dept. of Energy.
While it is good of him to chance his mind once he learned a bit more of what he's talking about, it doesn't diminish the fact that he and many other politicians are in a habit of going public with ideas and policies out of IGNORANCE. For some odd reason, many of them do not care that they make up their minds AND going public with such decision BEFORE they actually gather proper information about these things.
And if you think this is an isolated incident, you'd be wrong. I've highlighted several rather DUMB AND STUPID actions or comments made in public by these elected officials, all out of ignorance (read this and this, for example). I think that this is a common, standard-operating-procedure by many elected officials, that they really didn't do their homework in many decisions that they make.
Zz.
I have learned a great deal about the important work being done every day by the outstanding men and women of the Department of Energy. I have spoken several times to Secretary Moniz about the operation. I have spoken to his predecessors. And if confirmed, my desire is to lead this agency in a thoughtful manner surrounding myself with the expertise on the core function of the department. My past statements made over five years ago about abolishing the Department of Energy do not reflect my current thinking. In fact, after being briefed on some of the vital functions of the Department of Energy, I regret recommending its elimination.
While it is good of him to chance his mind once he learned a bit more of what he's talking about, it doesn't diminish the fact that he and many other politicians are in a habit of going public with ideas and policies out of IGNORANCE. For some odd reason, many of them do not care that they make up their minds AND going public with such decision BEFORE they actually gather proper information about these things.
And if you think this is an isolated incident, you'd be wrong. I've highlighted several rather DUMB AND STUPID actions or comments made in public by these elected officials, all out of ignorance (read this and this, for example). I think that this is a common, standard-operating-procedure by many elected officials, that they really didn't do their homework in many decisions that they make.
Zz.
Monday, January 16, 2017
Fermions and Bosons
Fermilab's Don Lincoln describes what bosons and fermions are, for those who don't know.
Zz.
Zz.
Labels:
Education,
Elementary Particles,
Quantum mechanics
Thursday, January 12, 2017
Imaging Fukushima Reactor Core Using Muons
If you are in the US, did you see the NOVA episode on PBS last night titled "The Nuclear Option"? If you did, did you miss, or not miss, the technique of imaging the Fukushima reactor core using the muon tomography developed at Los Alamos?
You see, whenever I see something like this, I want to shout out loud to the public on another example where our knowledge from high energy physics/elementary particle physics can produce a direct practical benefit. A lot of people still question whether our efforts in these so-called esoteric areas are worth funding. So whenever I see something like this, there should be a conscious and precise effort to point out that:
1. We had to first understand the physics of muons from our knowledge of the Standard Model of elementary particle.
2. Then those who do understand this often will start to figure out, often with collaboration of those in other areas of physics, of what could possibly be done with such knowledge.
3. And finally, they come up with a practical application of that knowledge, which originated out of an area that often produces no immediate and obvious application.
Things like this must be pointed out in SIMPLE TERMS to both the public and the politicians, because that is the only level that they can comprehend. I've pointed out previously many examples of the benefits that we get, directly or indirectly, from such field of study. It should be a requirement that any practical application should present a short "knowledge genealogy" of where the idea came from. It will be an eye-opener to many people.
Zz.
You see, whenever I see something like this, I want to shout out loud to the public on another example where our knowledge from high energy physics/elementary particle physics can produce a direct practical benefit. A lot of people still question whether our efforts in these so-called esoteric areas are worth funding. So whenever I see something like this, there should be a conscious and precise effort to point out that:
1. We had to first understand the physics of muons from our knowledge of the Standard Model of elementary particle.
2. Then those who do understand this often will start to figure out, often with collaboration of those in other areas of physics, of what could possibly be done with such knowledge.
3. And finally, they come up with a practical application of that knowledge, which originated out of an area that often produces no immediate and obvious application.
Things like this must be pointed out in SIMPLE TERMS to both the public and the politicians, because that is the only level that they can comprehend. I've pointed out previously many examples of the benefits that we get, directly or indirectly, from such field of study. It should be a requirement that any practical application should present a short "knowledge genealogy" of where the idea came from. It will be an eye-opener to many people.
Zz.
Monday, January 09, 2017
Mpemba Effect Is Still Hot After All These Years
OK, maybe not hot, but it is certainly at least lukewarm.
If you don't know anything about this, I've made several posts on the Mpemba effect before (read here, here, here, and here). Briefly, this is the effect where hot water is seen to freeze faster than cold water. Even after its purported discovery many years ago, the validity of this effect, and the possible explanation for it are still being debated.
Add this report to the body of discussion. It seems that there are new papers that are using molecular bonds in water as the possible explanation for this effect.
Zz.
If you don't know anything about this, I've made several posts on the Mpemba effect before (read here, here, here, and here). Briefly, this is the effect where hot water is seen to freeze faster than cold water. Even after its purported discovery many years ago, the validity of this effect, and the possible explanation for it are still being debated.
Add this report to the body of discussion. It seems that there are new papers that are using molecular bonds in water as the possible explanation for this effect.
Now researchers from the Southern Methodist University in Dallas and Nanjing University in China think they might have a solution - strange properties of bonds formed between hydrogen and oxygen atoms in water molecules could be the key to explaining the elusive Mpemba effect.I'm sure this will not be the last time we hear about this.
Simulations of water molecule clusters revealed that the strength of hydrogen bonds (H-bonds) in a given water molecule depends on the arrangements of neighbouring water molecules.
"As water is heated, weaker bonds break, and groups of molecules form into fragments that can realign to form the crystalline structure of ice, serving as a starting point for the freezing process," Emily Conover reports for Science News.
"For cold water to rearrange in this way, weak hydrogen bonds first have to be broken."
Zz.
Friday, January 06, 2017
The Brachistochrone Problem
There are many sources that describes this problem. Mary Boas also devoted a substantial portion of it in her classic text "Mathematical Methods in the Physical Sciences". Here, Rhett Allain describes it once more in his Wired article.
Laymen might find it fascinating just to know the shape of the path, while physics students might find it useful especially if you're just about to take class in Least Action principle.
Zz.
Laymen might find it fascinating just to know the shape of the path, while physics students might find it useful especially if you're just about to take class in Least Action principle.
Zz.
Thursday, January 05, 2017
Happy New Year!
A belated Happy New Year to everyone. I hope you all had a great holiday season.
Those of us in the US are facing a rather uncertain next few months. With the new administration taking office and the issue of science and science funding being trivialized during this last presidential election, no one knows where things are going. With Rick Perry slated to be nominated as the Secretary for the Dept. of Energy, it is like having the wolf looking after the sheep, since he had stated on more than one occasion of abolishing this part of the US govt. Sorry, but I don't think he has a clue what the DOE actually does.
This is not the first time someone who has no expertise in STEM is heading a dept. that deals with STEM. I've always wondered about the logic and rational of doing that. You never seen someone who is not an expert in finance or economics heading, say, the Treasury! So why is the DOE, which has been a significant engine in research, science, and technology, and which is the area that has been attributed to be responsible for the significant growth in our economy, being relegated as an ugly stepchild? Is it because STEM and STEM funding does not have a built-in constituent that will make public and political noise?
At this point, I have very low expectations for a lot of things during these next few years.
Zz.
Those of us in the US are facing a rather uncertain next few months. With the new administration taking office and the issue of science and science funding being trivialized during this last presidential election, no one knows where things are going. With Rick Perry slated to be nominated as the Secretary for the Dept. of Energy, it is like having the wolf looking after the sheep, since he had stated on more than one occasion of abolishing this part of the US govt. Sorry, but I don't think he has a clue what the DOE actually does.
This is not the first time someone who has no expertise in STEM is heading a dept. that deals with STEM. I've always wondered about the logic and rational of doing that. You never seen someone who is not an expert in finance or economics heading, say, the Treasury! So why is the DOE, which has been a significant engine in research, science, and technology, and which is the area that has been attributed to be responsible for the significant growth in our economy, being relegated as an ugly stepchild? Is it because STEM and STEM funding does not have a built-in constituent that will make public and political noise?
At this point, I have very low expectations for a lot of things during these next few years.
Zz.
Wednesday, December 28, 2016
Sidney Drell And Vera Rubin
We lost two incredible and important figures in physics during this holiday season.
Sidney Drell, the elementary particle theoretical physicist responsible for the Drell-Yan process, passed away on Dec. 21, 2016. As important as his work in physics, he was also a central figure in the effort of nuclear disarmament. His accomplishments and efforts are just too numerous to list here, and you should do yourself a favor and read about him. He has no doubt had a hand in shaping our world today.
We lost Vera Rubin on Christmas day. She was one of the first astronomers to make the Dark Matter detection, and someone whom I thought should have already been awarded the Nobel Prize. So this year, we lost two extremely strong women candidates for the Nobel prize, Rubin and Deborah Jin.
Zz.
Sidney Drell, the elementary particle theoretical physicist responsible for the Drell-Yan process, passed away on Dec. 21, 2016. As important as his work in physics, he was also a central figure in the effort of nuclear disarmament. His accomplishments and efforts are just too numerous to list here, and you should do yourself a favor and read about him. He has no doubt had a hand in shaping our world today.
We lost Vera Rubin on Christmas day. She was one of the first astronomers to make the Dark Matter detection, and someone whom I thought should have already been awarded the Nobel Prize. So this year, we lost two extremely strong women candidates for the Nobel prize, Rubin and Deborah Jin.
Zz.
Monday, December 19, 2016
Antihydrogen Looks Just Like Hydrogen
The ALPHA collaboration at CERN has measured the first ever 2s-1s transition in antihydrogen atoms, and it looks like the Standard Model and CPT symmetry are still correct!
I'm sure there will be many more to come. The ability to store antihydrogen long enough to study it is a major accomplishment in itself.
Zz.
Carrying out the whole procedure 11 times, the group found that on average just under 60% of antiatoms left the trap with the laser tuned to the 1s-2s transition, while no antiatoms (within the bounds of statistical error) dropped out when the laser was tuned to a different frequency or when it was switched off. The researchers say that the antiatoms underwent the transition at the expected frequency and therefore behaved no differently from normal hydrogen.
I'm sure there will be many more to come. The ability to store antihydrogen long enough to study it is a major accomplishment in itself.
Zz.
Wednesday, December 07, 2016
"Germany's Wildly Complex Fusion Reactor Is Actually Working" - Fake News?
Does qualify as "Fake news", or are they just being stupid?
I posted yesterday about the successful test of the Wendelstein 7-X Stellerator magnetic field. It definitely should deserve the media publicity, because the topology of the magnetic field is very complex and very crucial to how they intend to hold the plasma that they will generate. But this is simply just ONE STEP towards the operation of this machine. They still haven't achieve yet what they intend to do.
So it is with a bit of a dismay that I read news reports that somehow indicated that this "fusion reactor" is "actually working"! Now, I wouldn't have paid much attention had this come from some obscure site, but this one actually came from Popular Mechanics!
I posted yesterday about the successful test of the Wendelstein 7-X Stellerator magnetic field. It definitely should deserve the media publicity, because the topology of the magnetic field is very complex and very crucial to how they intend to hold the plasma that they will generate. But this is simply just ONE STEP towards the operation of this machine. They still haven't achieve yet what they intend to do.
So it is with a bit of a dismay that I read news reports that somehow indicated that this "fusion reactor" is "actually working"! Now, I wouldn't have paid much attention had this come from some obscure site, but this one actually came from Popular Mechanics!
However, the stellerator design is still relatively untested, so a group of researchers spent the past year studying the W7-X reactor to ensure that it was working the way it was supposed to. They found an incredibly small error rate, less than 1 in 100,000, which the researchers characterized as "unprecedented accuracy."This is good news for the W7-X reactor, which was intended as a proof-of-concept for the stellerator design. Now that the researchers know the accuracy of the reactor's magnetic fields, they can begin building new reactors that focus on efficiency.
I'm sorry, but if you don't know any better, you'd think that this darn thing is now working, and they're now going to design "new reactors" with better performance.
Bullcrap!
How dense can one be to get this report wrong? The actual paper, which one can read freely online, clearly indicated that this was a test of the complicated magnetic field, not the actual working of the reactor.
I would not be surprised if this is nothing more than a wrong piece of information that got passed around. I see Science Alert having the same type of headlines in their report.
All of these are misleading, and worst still, they are misleading the public who do not have the awareness of what is going on. And this is sad because the public often relies on these type of news sources, and yet, they are being given, at best, a misleading information.
Zz.
Monday, December 05, 2016
Confirmation Of Wendelstein 7-X Magnetic Field
I mentioned a while back that Germany's Wendelstein 7-X Stellerator was about to go on with their tests. One of the most novel aspect of this fusion machine is the complex topology of its magnetic field.
We now have a report that confirms the topology of this magnetic field, with an agreement of better than 1:100,000. The field lines that they saw as shown in Fig. 2 of the paper is astounding and science-fictiony!
Well done, people!
Zz.
We now have a report that confirms the topology of this magnetic field, with an agreement of better than 1:100,000. The field lines that they saw as shown in Fig. 2 of the paper is astounding and science-fictiony!
Well done, people!
Zz.
Monday, November 28, 2016
What Is The Big Deal With This Math Problem?
For at least a year now, I've seen this math problem being floated about the various new websites. And I don't understand why it is such a big deal.
The problem involves a simple math problem that many students first learned in an intro algebra class:
Now, any child learning something like this would have to also learn about the SEQUENCE of operations that one has to perform to do this correctly. If you simply start to enter this into your calculator in order that it is written, you'll get the wrong answer.
And of course, you have to know that dividing by 1/3 is equivalent to multiplying by 3.
There are many mnemonic guides that one can use to know which one to perform first. In this case, you first perform the division, thus simplifying the equation into:
9 - 9 + 1 = ?
which will obviously leave you with the answer of 1.
This problem is getting rather a lot of publicity because it claims that a lot of people didn't get the right answer for something that seemingly looks very simple. My response to that is: Yeah, so?
When one learns this rule in school, one is given many similar problems of this type. This is not an unusual problem, and certainly something a lot of people will get wrong if they don't remember what the rule is. This is not surprising.
But why is it getting this much publicity?
Zz.
The problem involves a simple math problem that many students first learned in an intro algebra class:
Now, any child learning something like this would have to also learn about the SEQUENCE of operations that one has to perform to do this correctly. If you simply start to enter this into your calculator in order that it is written, you'll get the wrong answer.
And of course, you have to know that dividing by 1/3 is equivalent to multiplying by 3.
There are many mnemonic guides that one can use to know which one to perform first. In this case, you first perform the division, thus simplifying the equation into:
9 - 9 + 1 = ?
which will obviously leave you with the answer of 1.
This problem is getting rather a lot of publicity because it claims that a lot of people didn't get the right answer for something that seemingly looks very simple. My response to that is: Yeah, so?
When one learns this rule in school, one is given many similar problems of this type. This is not an unusual problem, and certainly something a lot of people will get wrong if they don't remember what the rule is. This is not surprising.
But why is it getting this much publicity?
Zz.
Sunday, November 20, 2016
What So Spooky About Quantum Entanglemnt?
I hate to keep beating a dead horse, but this question DOES keep popping up regularly on many websites and forums. And when a new article tries to explain this again, it bares repeating.
This article tries to explain what is so "spooky" about quantum entanglement. The "spookiness" comes from Einstein's description of quantum mechanics which he showed, via the EPR-type measurement, that information about a quantum property can be "transferred" instantaneously between entities across space.
You'll notice that in the article, the author had to go back and explain the concept of superposition of states. This is what makes this type of phenomenon different than the classical phenomenon.
Zz.
This article tries to explain what is so "spooky" about quantum entanglement. The "spookiness" comes from Einstein's description of quantum mechanics which he showed, via the EPR-type measurement, that information about a quantum property can be "transferred" instantaneously between entities across space.
You'll notice that in the article, the author had to go back and explain the concept of superposition of states. This is what makes this type of phenomenon different than the classical phenomenon.
If you had been following this blog for a while, this is the same attempt that I made to explain quantum entanglement before. This is because most people who are just trying to understand this only pay attention to the "entanglement" aspect of it, i.e. a property being "linked" over a distance, rather than actually understanding the superposition concept, which is actually more well-established. It is the presence of superposition, and the lack of classical realism on a system (before a measurement) that separates this from an ordinary classical conservation-of-quantity phenomenon.Let’s go over the issue of entanglement to start. The experiment is normally done with photons: you pass a single quantum of light through a specialized material (e.g., a down-conversion crystal) which splits it into two photons. These photons will be entangled in a particular sense, where one has a spin, or internal angular momentum, of +1, and the other has a spin of -1. But you don’t know which is which. In fact, there are some experiments you can do where, if you had large numbers of these photons, you’d see a difference between:
- the statistical results if the spin was +1,
- the statistical results if the spin was -1,
- or the statistical results if the spin was undetermined.
Zz.
Friday, November 11, 2016
The APS In Hot Doo-Doo Over Trump Congratulatory Statement
OK, I missed this, and only now got wind of it.
The APS issued a congratulatory statement to Donald Trump for winning the US Presidency election, along with urging him to invest in science and technology.
Unfortunately, that congratulatory message didn't go well with a lot of the members, and that message has now been taken down.
The APS issued a congratulatory statement to Donald Trump for winning the US Presidency election, along with urging him to invest in science and technology.
Unfortunately, that congratulatory message didn't go well with a lot of the members, and that message has now been taken down.
The statement smacked many readers as tone-deaf because of Trump’s antagonism to science, as evidenced by his statements suggesting that climate change is a hoax, endorsing online polls over statistically modeled ones and linking vaccines to autism.According to Prescod-Weinstein, the slogan “Make America Great Again” is problematic because it presupposes that the United States was great when African-Americans were “more likely to be hanged from a tree than welcomed in the physics community” and when Nazi war criminals “became central to the American scientific establishment.”
“If APS’s leadership had any imagination — or concern for those of us who are being threatened by emboldened racists/transphobes/etc.,” she continued, “they would have said, ‘We urge President-elect Trump to finally actually make America great through the allocation of resources that will combat discrimination and hate in all their forms.’”
All I can say is that these next few years are going to be "interesting".
Zz.
Monday, October 10, 2016
Physics In "Doctor Strange"
Adam Frank, a physics professor at the University of Rochester, talks about being a consultant for the upcoming Marvel movie "Doctor Strange".
I suppose the biggest and most dicey issue that he had to deal with is how to deal with "consciousness", because as he stated, we actually do not have a concrete description of it. This is where many movies, and many pseudoscientists, allow themselves wide liberty at abusing the concept.
I will see "Doctor Strange" when it comes up, and I'll see for myself how the movie deals with this.
Zz.
I suppose the biggest and most dicey issue that he had to deal with is how to deal with "consciousness", because as he stated, we actually do not have a concrete description of it. This is where many movies, and many pseudoscientists, allow themselves wide liberty at abusing the concept.
I will see "Doctor Strange" when it comes up, and I'll see for myself how the movie deals with this.
Zz.
Thursday, October 06, 2016
Detecting Particles By Seeing Them Move Faster Than Light
No, this is not a topic on superluminal particles. Rather, it is an article on how we detect particles by using faster-than-light particles in a medium, i.e. by observing the Cherenkov radiation.
The article listed several detectors that make use of this effect, but it is missing A LOT more. Practically all neutrino detectors use this principle (i.e. SuperKamiokande). Auger Observatory also looks out for these Cherenkov radiation.
But the part that I think should fascinate the layperson is when the speed of various things are listed, up to the most accurate decimal places:
Zz.
But photons only move at that perfect speed-of-light (c) if they’re in a vacuum, or the complete emptiness of space. Put one in a medium — like water, glass, or acrylic — and they’ll move at the speed of light in that medium, which is less than 299,792,458 m/s by quite a bit. Even air, which is pretty close to a vacuum, slows down light by 0.03% from its maximum possible speed. This isn’t that much, but it does mean something remarkable: these high-energy particles that come into the atmosphere are now moving faster than light in that medium, which means they emit a special type of radiation known as Cherenkov radiation.
The article listed several detectors that make use of this effect, but it is missing A LOT more. Practically all neutrino detectors use this principle (i.e. SuperKamiokande). Auger Observatory also looks out for these Cherenkov radiation.
But the part that I think should fascinate the layperson is when the speed of various things are listed, up to the most accurate decimal places:
It’s true that Einstein had it right all the way back in 1905: there is a maximum speed to anything in the Universe, and that speed is the speed of light in a vacuum (c), 299,792,458 m/s. Cosmic ray particles can go faster than anything on Earth, even at the LHC. Here’s a fun list of how fast various particles can go at a variety of accelerators, and from space:Just notice how much energy we had to put in to, say, the proton in going from 0.99999954c to 0.9999999896c. And then, notice how high of an energy cosmic rays have when compared to the LHC. If these types of collisional energy can create "catastrophic blackholes", we would be gone by now, thankyouverymuch!
- 980 GeV: fastest Fermilab proton, 0.99999954c, 299,792,320 m/s.
- 6.5 TeV: fastest LHC proton, 0.9999999896c, 299,792,455 m/s.
- 104.5 GeV: fastest LEP electron (fastest accelerator particle ever), 0.999999999988c, 299,792,457.9964 m/s.
- 5 x 10^19 GeV: highest energy cosmic rays ever (assumed to be protons), 0.99999999999999999999973c, 299,792,457.999999999999918 m/s.
Zz.
Subscribe to:
Posts (Atom)
