Posted on 09/13/2021 1:50:19 PM PDT by blam
In a demonstration of Einstein’s E=mc2, collisions of light yielded electrons and positrons "
Collide light with light, and poof, you get matter and antimatter. It sounds like a simple idea, but it turns out to be surprisingly hard to prove.
A team of physicists is now claiming the first direct observation of the long-sought Breit-Wheeler process, in which two particles of light, or photons, crash into one another and produce an electron and its antimatter counterpart, a positron. Like a discussion from an introductory philosophy course, the detection’s significance hinges on the definition of the word “real.” Some physicists argue the photons don’t qualify as real, raising questions about the observation’s implications.
Predicted more than 80 years ago, the Breit-Wheeler process had never been directly observed, although scientists have seen related processes, such as light scattering off of light (SN: 8/14/17). New measurements from the STAR experiment at Brookhaven National Laboratory’s Relativistic Heavy Ion Collider match predictions for the elusive transformation, Brookhaven physicist Daniel Brandenburg and colleagues report in the July 30 Physical Review Letters.
“The idea that you can create matter from light smashing together is an interesting concept,” says Brandenburg. It’s a striking demonstration of the physics immortalized in Einstein’s equation E=mc2, which revealed that energy and mass are two sides of the same coin.
Whether the observation truly qualifies depends on whether the photons are considered “real,” as demanded by the Breit-Wheeler process, or “virtual.” In particle physics, virtual particles are ones that appear only for brief instants and don’t carry their normal masses.
Photons from a commonplace source of light, like a lightbulb or a laser, are real, physicists agree. But the bona fides of Brandenburg and colleagues’ photons are up for debate. That’s because the light the team is colliding comes from
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(Excerpt) Read more at sciencenews.org ...
Running low on funding, I see!
There goes the first Law of Thermodynamics.
Sounds like Genesis 1 to me.
Light lives matter
There goes the first Law of Thermodynamics.
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Yeah...I thought matter to energy was a one-way street...no converting it back.
Of course photons are real
How do you think they make photon torpedoes?
Duh!!!
🤪🤪🤪
How dare they, denigrating photons like that.
Funny how science is showing that something incredible (not randomly accidental) happened long ago.
“How dare they, denigrating photons like that.”
I know, right?! Telling photons that they don’t matter.
No. Frist law is about conservation of energy. Einstein's mass energy equivalence states that there is no issue here. Now, there are other conservation laws as well - charge conservation [so for every electron you also make an anti-electron, a positron] angular momentum / spin conservation.
So, for instance to make an electron - positron pair out of vacuum requires at least the rest mass energy of two electrons which is 2 x 511 keV [measuring mass as energy per Einstein's E=mc2 formula and measuring energy in electron volts, which is usual in high energy physics].
Exatly!
Photonic dissonance...
Can’t they all just get along!
The first law of thermodynamics is a version of the law of conservation of energy, adapted for thermodynamic processes, distinguishing two kinds of transfer of energy, as heat and as thermodynamic work, and relating them to a function of a body’s state, called internal energy.
The law of conservation of energy states that the total energy of an isolated system is constant; energy can be transformed from one form to another, but can be neither created nor destroyed.
I guess the problem with photons is that they’re just too white.
Mass and energy are equivalent and there are a gazillion experiments showing that.
It is well known that a U235 nucleus has a greater mass than do the constituent products when it decays through spontaneous fission. The difference in masses exactly equals the kinetic energy of the decay fragments and the energy of any gamma rays emitted.
Yup.
On the very first day God created only one thing: light.
That was it. Just light.
And he separated that light (matter?) from the darkness (anti-matter?).
Sounds to me like that was the foundation for everything that followed.
Sounds like Genesis 1 to me, too. God is light
While many math equations have been proven correct, others have been proven incorrect. There is a reason theoretical physics is call theory.
Also, I don't understand the latest theory of what gravity is. Can someone explain it in layman terms?
Then you have the basketball size singularity that caused the big bang. Yes, I get the reverse math of the known universe expanding according to red shift. How and why did the super-heated basketball appear with only 2 elements?
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