count_of_monte_carlo @ count_of_monte_carlo @lemmy.world

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in the photon's frame of reference

There are no valid inertial frames for an object moving at the speed of light. The idea that “a photon doesn’t experience time” is a common, but misleadingly incorrect statement, since we can’t define a reference frame for it. Sometimes this misconception can be useful for conveying some qualitative ideas (photons don’t decay), but often it leads to contradictions like your question about Hawking Radiation for black holes.

Yes, the wavelength of photons will be preserved if they travel through non-expanding space. If the photon is emitted by a source that’s in motion with respect to a detector, there could still be redshift or blueshift from the relativistic Doppler effect. This would only depend on the relative velocity between the emitter and observer, and not on the distance the photon traveled between them.

This falls a bit outside my wheelhouse but I believe the answer is no. The established symmetries in particle physics are all associated with the quantum mechanical state of a particle (charge, parity, etc) and to my knowledge there isn’t an “information” quantum number.

The closest you might get to this is quantum information theory, where information is encoded in other physical characteristics (spin, parity, energy, etc). In this sense information is more of an emergent phenomenon than a fundamental property.

Sorry, physics can be cruel sometimes :(

Hah tell me about it. The 2017 neutron star merger happened while I was writing a proposal for an experiment where the physics was sort of related. So of course I completely reframed the proposal around that event, and it got funded! And that was just a few years ago, right?

Man I really need to publish the results of that project…

Certainly! You can see discrete emission lines from the ionized air molecules, which only occurs because of quantum physics. I realize that’s not what you’re asking though.

I did a quick calculation and for a plasma torch (~27000 Kelvin) and assuming air molecules, the average velocity of the plasma ions would only be like 6000 m/s. That’s 0.001% the speed of light, so you aren’t going to see any relativistic effects.

First a caveat: An object with mass can’t move at the speed of light, but it could move at speeds arbitrarily close to that.

The most successful model of gravity isGeneral Relativity, which treats gravity as a curvature of 4-dimensional space time. Gravity’s influence travels at the speed of light. There’s a classic thought experiment that sort of answers your question: what would happen if the sun was teleported away? The answer is the earth would continue to orbit around the spot the sun was for 8 minutes, and we would continue to see sunlight for that same amount of time since that’s how long it takes light to travel that distance. Then after 8 minutes the sun would disappear and the first “lack of gravity” would reach us, and things would be bad for earth :(

The fact that gravity travels at the speed of light actually leads to an interesting phenomenon: Gravitational waves If a massive object rapidly accelerates (or decelerates), for example a star sized mass moving quickly and then coming to an abrupt stop, it will emit a ripple in space time called a gravitational wave that will travel outward at the speed of light.

It was big news about a decade ago when gravitational waves were first detected by LIGO, a series of large interferometers that look for expansion/contraction in spacetime. Their first detection was the collision of 2 black holes; as the black holes spiral around each other and eventually merge, they emit oscillating waves with increasing frequency. They made a cool video showing how the frequency increases by converting it to sound.

Since then LIGO and VIRGO (similar European collaboration) have detected multiple gravitational waves from the collision of black holes and neutron stars. So not only are gravitational waves a neat validation of general relativity, they’re actually being used to do astronomy.

Thanks! I forgot to put the exclamation mark at the front of the link. Hopefully it works now

lmk if there's a better community to ask this in

Shameless plug: you could try !askscience@lemmy.world

The Milwaukee Protocol is a treatment plan that is essentially a more advanced version of what you’re asking. The patient is put in a medically induced coma and then given antivirals and IV fluids, which avoids the issue of hydrophobia.

It got a lot of press because one person survived on it (a big deal given that rabies is a death sentence once symptoms appear) but this success hasn’t been reproduced with other patients. A paper on the protocol has a remarkably blunt title: Critical Appraisal of the Milwaukee Protocol for Rabies: This Failed Approach Should Be Abandoned.

Hi there! Can you please remove the word “retarded” in your first sentence? This word is now generally considered a slur, which runs afoul of rule 6 “Use appropriate language and tone. Communicate using suitable language and maintain a professional and respectful tone.”

I second the other poster’s suggestion to look into nonlinear optics. A really common application is frequency doubling, also known as second harmonic generation, which doubles the energy of the photons. So an 800 nm laser (red) can be converted to 400 nm (green) with this method.

The National Ignition Facility (NIF) actually uses frequency tripling of the laser pulses right before they enter the target chamber. That’s pretty wild, I had intended to look up NIF to give a high profile example of second harmonic generation, I hadn’t realized they were actually doing third harmonics.

Another optics-based phenomenon that I think maybe strays too far from the intent of your initial question, but is too cool not to share, is laser Wakefield acceleration. A very high power laser pulse will push electrons out of its path in plasma or materials via the ponderomotive force. This charge separation creates electric field gradients on the order of billions of volts per centimeter, which can accelerate electrons or other charged particles to relativistic energies. So you can start with a green laser pulse and wind up producing gamma-ray beams, either by slamming the electrons into a stopping material or by Compton scattering other low energy photons off the relativistic electrons.

But in order to do that photon actually needs to be created and travel from one particle to another.

The electromagnetic force is mediated by virtual photons. These don’t exist as free particles, such as a photon emitted by a light source, but only as an intermediate particle. Because they’re only intermediate states, virtual photons can have non-physical energies (so long as they’re within the uncertainty principle), resulting in some having an effective mass. Suffice it to say virtual photons are quite distinct from real ones! Technically, I believe you could have some of the basic features of the em force (namely attraction/repulsion by 2 point charges) with just virtual photons. Things get tricky once charges begin accelerating though, as this leads to the emission of real photons.

If Higgs works in a similar way also being a boson

The short answer is, it doesn’t. The Higgs Field gives mass to fundamental particles. Existing in that field causes certain particles to have mass due to their coupling to the field. The W and Z weak gauge bosons gain mass through electroweak symmetry breaking, quarks and leptons gain mass through a different coupling. I realize this is a very unsatisfying answer as to “how” the Higgs field creates mass, but the mechanism involves some complex math (group theory and non-abelian gauge theory), so it kind of defies a simpler explanation. Regardless, it’s through interactions with the Higgs field (which can exist without any Higgs bosons around) that fundamental particles gain mass. The search for the Higgs boson was just to confirm the existence of the field, because while the field can exist without Higgs bosons present it must be possible to excite it sufficiently to create them.

Going back to your original question: these particles have almost certainly been created “naturally” in high energy collisions between particles and matter. Nature can achieve much higher energies than our particle accelerators. The highest energy particle ever observed was a cosmic ray. However, Higgs bosons are extremely short lived, with a lifetime of 10^-22 seconds. So whenever they’re created, they don’t stick around for a meaningful amount of time.

Im dealing with all rule breaking behavior. The unsourced comments have now been removed as the user is unable to provide a source to backup their claim. The comments that break civility rules, including this one, are also being removed.

Please report rule 9 violations so that we can act on them.

The source provided by another user gives a definitive counter argument.

From the article: “ The wheat kernel contains 8%–15% of protein, from which 10%–15% is albumin/globulin and 85%–90% is gluten (Fig. 1).1 Gluten is a complex mixture of hundreds of related but distinct proteins, mainly gliadin and glutenin. Different wheat varieties vary in protein content and in the composition and distribution of gluten proteins.”

This comment is on the edge for rule 6 “Use appropriate language and tone.” I’d appreciate it if you’d edit the language to be more professional.

Thank you for providing a source in your comment!

Per rule 9, please provide a credible source for the statement “Gluten doesn’t appear in nature on its own”

Per rule 9, please provide a source for the statement that gluten is a “synthetic or semi-synthetic organic polymer”.

Berkeley still has a cyclotron, though it’s a little newer (build in the 60’s) and much bigger.

I believe the idea is that a single bright star in the frame (the guide star) is used for selecting the frames. The point spread function (PSF) is just going to be some function that describes the blurred shape you would observe with the detector for an input point source. You then select frames in which the guide star is well centered, compared to its overall distribution.

I think your guess on “sync-resampled” is correct. They increased the “resolution” by a factor of 4, so that when they realign the chosen frames to center the guide star, they can do so at a sub-pixel precision.

You may want to check out chapter 3 in the thesis, particularly section 3.5.3. The give a lot more detail on the process than you’ll be able to find in the paper. A well-written PhD thesis can be 1000x more valuable than the journal article it ultimately produces, because it contains all the specific details that can be glossed over in the final paper.