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a reply to: BASSPLYR

Photon is generally considered its own antiparticle. And you're right in that electromagnetism on its own is time reversible.

And that's pretty much what the phase-conjugate stuff is about---effectively generating a time-reversed signal. Time-reversal is a better name than phase conjugate. There is a wikipedia page that distinguishes them but I don't really buy the difference at a fundamental level:

It is distinguished from Time Reversal Signal Processing by the fact that phase conjugation uses an holographic or parametric pumping whereas time reversal records and re-emits the signal using transducers.[1]

so really it's whether the time-reversal effectively happens automatically by atomic physics or by some more constucted technological device.

a reply to: mbkennel

thank you mbkennel.

I always learn something from you that helps me better understand physics.
for a second I though you were going to tear into me and go wth man you know damned well that's not how physics works stop thinking out of the box. thanks for going easy on me.

I have another one. What is the mechanism that allows a quark to transform into another with a differing mass? Or for a Top quark (which has roughly the mass of a tungsten atom) to bond with other quarks which also have mass, and produce a particle with less mass than the sum of the quarks in it?

originally posted by: pfishy
I have another one. What is the mechanism that allows a quark to transform into another with a differing mass?

I'm not an expert on this, but I think quark flavor changes require weak force interactions.

Or for a Top quark (which has roughly the mass of a tungsten atom) to bond with other quarks which also have mass, and produce a particle with less mass than the sum of the quarks in it?

Strong force, which is more attractive the further away quarks get.

originally posted by: pfishy
I have another one. What is the mechanism that allows a quark to transform into another with a differing mass?

I'm not an expert on this, but I think quark flavor changes (e.g. top to bottom) require weak force interactions, but color interactions are strong force.

Or for a Top quark (which has roughly the mass of a tungsten atom) to bond with other quarks which also have mass, and produce a particle with less mass than the sum of the quarks in it?

Strong force. Like nuclei sticking together; the mass contribution of a neutron bound is less than a free neutron.

a reply to: mbkennel

Hmm. Thanks for the answer. Still puzzles me, but that's a better understanding than I had when I asked the question.

originally posted by: pfishy
I have another one. What is the mechanism that allows a quark to transform into another with a differing mass? Or for a Top quark (which has roughly the mass of a tungsten atom) to bond with other quarks which also have mass, and produce a particle with less mass than the sum of the quarks in it?

This is a bit complicated but I'll try to make it simple. Let's look at a proton and nuetron they are made from three quarks.Their masses are quite close, but they are noticeably different. Well how can this be you ask? A proton is made up of two Up quarks and a Down quark while a neutron is made from two Down quarks and an Up quark. If protons and neutrons only had quarks in them it would be easy algebra to get the quark masses. However, there is a family of lighter particles called Pions that are made from pairs of quarks.Protons and neutrons do not have the same mass.
These pions when created can cause are particle to have a different mass. Normally we wouldn't see them but they show up in high energy collisions such as a collider.Pions have masses of 139.6 MeV for Pi+ or Pi- and 134.975 MeV for the Pi0 or Pi zero (neutral) and this is the key depending on which quarks we pair decides what pi on we get. If I break apart a quark pair and add another quark my mass can indeed be lower. Let's go back to the proton we have 3 bonds for quarks an up up quark an up and down quark and a down and up quark each creating their own pions. Does that make sense?

originally posted by: mbkennel
a reply to: Choice777
For example: vixra.org...

Oh dear, just look at those references!

[1] Self-cite. Unpublished. Not peer-reviewed.
[2] Self-cite. Personal website. Not peer-reviewed.
[3] Self-cite. Self-published. Not peer-reviewed.
[4] Self-cite. Inactive website. Not peer-reviewed.
[5] Self-cite. Defunct fringe journal with no impact factor.
[6] Self-cite. Non peer-reviewed fringe journal. Their mission statement says they will literally publish anything verbatim.
[7] Self-cite. See: [6]
[8] Woo hoo! A non self-cite! To a book. Not in English...
[9] Woo hoo! Another non self-cite! To another book
[10] Woo hoo! We're on a roll! Another non self-cite! To a... neurology paper??
[11] Self-cite. Unpublished. Not peer-reviewed.
[12] Good news: non self-cite. Bad news: to an upmarket Wikipedia
[13] Good news: non self-cite. Bad news: I can't even find this paper or supposed journal anywhere

An unreviewed paper with over 60% self citations, mostly to unreviewed work and personal websites? Yeah, doesn't pass the smell test.

a reply to: dragonridr

So, protons are composed of 3 pions, not 3 quarks? I could have sworn it was just 3 quarks.
Dragonridr, I really appreciate you. You have the ability to occasionally make my head spin, which doesn't happen often.
But, does an up up pion have a mass that is a different value of the sum of the 2 up quarks it consists of? That's what twists my noodle. A top quark can be a component of a particle with less mass than the top quark alone. And how, as mbkennel explained above, can the mass contribution of a bound neutron be less than the mass of an unbound neutron?
In bonding, it there some interaction which takes energy from the constituent quarks, thus lowering their mass?

Arbitrageur and mbkennel, you also have the ability to leave me temporarily slack-jawed. Not just dragonridr. Kudos all around. And thanks.

originally posted by: pfishy
a reply to: dragonridr

So, protons are composed of 3 pions, not 3 quarks? I could have sworn it was just 3 quarks.

As explained in this video, the quarks only account for about 1% of the total mass of a proton, so it's not just 3 quarks and it could also be 5 or 7 at any point in time as also explained in the video, but even at those points in time when there are more quarks, most of the mass of the proton is not accounted for by quarks:

Your Mass is NOT From the Higgs Boson

I have a basic question. Is it true that there will never ever be a way to produce hydrogen in an efficient manner?

originally posted by: network dude
I have a basic question. Is it true that there will never ever be a way to produce hydrogen in an efficient manner?

The problem with hydrogen as a primary fuel is that it's very very reactive. So over the eons, there just isn't any left free. It's tied up with things, a lot of it water, where it's the end point of a combustion reaction.

Thus you can't mine it, or pump it up, and in order to get any you have to pry it loose from a chemical bond that may (oil, say) or may not (water) have any chemical energy left to extract. This means you aren't going to have a lot of luck making it a primary power source like, say, petroleum or fission power.

You can get it with less energy input if you strip it from hydrocarbons, so you can make hydrogen from petroleum pretty easily, but in terms of efficiency, you've lost the combustion energy you would have gotten from the carbons, so you're chucking a bunch right there at the extraction facility. And stripping it from water invariably loses some of the electrical energy input as Joule heating of the water.

However, there are fairly efficient electrolyzers, PEM comes to mind, which is sort of a reverse fuel cell. PEM is, however, cranky and so far the polymer tends to be easily contaminated and somewhat short-lived, but you'd hope that a lot of material science work could fix that eventually.

No matter how efficient though, it's never going to give you hydrogen for less energy input than you'll get from burning it, so it's not 'over unity'. What it COULD be useful for is energy storage from sources that are less than dependable 24/7, such as wind or solar. A sort of science-fictiony cheap PEM/fuel cell combo machine that was 95% efficient, uncranky, and durable would make battery banks go bye-bye for home solar.

You could obviously also store it in metal hydrides for auto fuel. But it's questionably efficient if you're making the hydrogen with a primary power source like a gas-fired plant or a nuclear reactor, because then you have to ask if it's not preferable to skip the conversion steps and just have electric cars.

a reply to: network dude
This sounds promising:

Hydrogen production breakthrough could herald cheap green energy

Scientists have taken a major step forward in the production of hydrogen from water which could lead to a new era of cheap, clean and renewable energy.

Chemists from the University of Glasgow report in a new paper in Science today on a new form of hydrogen production which is 30 times faster than the current state-of-the-art method. The process also solves common problems associated with generating electricity from renewable sources such as solar, wind or wave energy.

That was last September so it's still a bit soon to see how viable the technology really is, but even if this doesn't pan out, I think as oil prices rise with scarcity, producing hydrogen using solar cells can only become more economically viable in the future even if the economics aren't that great today.

There are also advances being made in the efficiency of solar cells, and there's still more upside to those improvements.

Thank you both for the replies. My reasoning is that hydrogen, when burned as a fuel, outputs water. (in a basic sense to my understanding) so while we use the hydrogen for fuel, we put it back into the system when used. If that is incorrect, please explain as best you can as if you were talking to an idiot. (for my sake)

If the mechanism used to produce the hydrogen, was something like solar power, or wind, or geothermal, wouldn't it be more along the lines of a renewable energy source?

originally posted by: network dude
Thank you both for the replies. My reasoning is that hydrogen, when burned as a fuel, outputs water. (in a basic sense to my understanding) so while we use the hydrogen for fuel, we put it back into the system when used. If that is incorrect, please explain as best you can as if you were talking to an idiot. (for my sake)

If the mechanism used to produce the hydrogen, was something like solar power, or wind, or geothermal, wouldn't it be more along the lines of a renewable energy source?

Water's not an energy source, because it's burnt. There's no chemical energy left at all. So you can't really think of water as a renewable energy source, or an energy source at all.

What it IS is a chemical that you're using to store energy by breaking its bonds. It's convenient because it's a non-toxic chemical, and it's readily available, and cheap, and the combustion end product is...water.

But it's not an energy source at all. The energy source is the solar cells, or the wind generator, or the geothermal power plant. The water's nothing but a lossy storage medium.

a reply to: Bedlam

So, if you have a car that runs on hydrogen, what comes out of the exhaust?

And the creation question comes from the limited understanding that to get hydrogen, you need to separate it from the Oxygen in H2O. Or is there another way to get it?

Sorry for all the questions, but I am trying to understand the mindset that let Honda and Toyota spend money to create hydrogen powered cars if it takes more fuel to create the hydrogen than if you just used gas. It seems someone like an engineer would have mentioned it to them at some point.

I had been told in the past that the process to separate hydrogen was inefficient and would always be that way because of the laws of physics.

a reply to: Arbitrageur

Following the particle codes for this universe
Is it possible to extract or remove electrons
from atoms to compress matter to travel through
and then return the extracted electrons to the matter
in order to return the coded region back to its original form

So you would emit a laser or wave or rings flow of electron displacement material that would compress basically space. Then somehow travel through the compressed space. And once travel is completed re expand "space"

1 is not licensed in Quantum Physics, so its understood if the question does not "fit"

The electron field collapse allows for neutron and proton particle matter distance manipulation compression expansion...

originally posted by: network dude
a reply to: Bedlam

So, if you have a car that runs on hydrogen, what comes out of the exhaust?

Water, of course. The next question is, how do you get the hydrogen? And that answer is - you separate it from water, using more energy than you will get back later. Or, you separate it from petroleum feed stock or natural gas, but then you also lose the energy from combusting the carbons. And that's pretty much it.

And the creation question comes from the limited understanding that to get hydrogen, you need to separate it from the Oxygen in H2O. Or is there another way to get it?

Nope. There are, to be sure, even more indirect and more lossy ways like the guy upthread who thought it was a great idea to refine aluminum, then use the refined metal to pull the oxygen off water molecules, releasing hydrogen, then re-refine the aluminate sludge. But you lose something like 80% of your energy input that way.

Sorry for all the questions, but I am trying to understand the mindset that let Honda and Toyota spend money to create hydrogen powered cars if it takes more fuel to create the hydrogen than if you just used gas. It seems someone like an engineer would have mentioned it to them at some point.

I had been told in the past that the process to separate hydrogen was inefficient and would always be that way because of the laws of physics.

It's one of those burning questions. And it basically comes down to the degree of inconvenience you want to subject the auto driver to. If your trips are mostly somewhat short, then you will be better served by electric cars. There you store the power in the form of chemical states inside the battery pack. You have losses in the charger, and losses in the charging battery, and losses in the discharging battery, the electronics that handle the power, and the motors. But they are well-known and fairly minimal, with steady improvements in every area as the years go by.

But charging takes time. And modular batteries are an idea that never seems to take off. That might be fixed by faster charging chemistries like nano-particulate electrodes, but that is also a butt pain in other ways and they tend to have more losses, so it's a time vs efficiency wash. And in all electric cars, you will have to replace/rebuild the battery, which will take energy and will have a cost associated with it. Better batteries/chemistries may mitigate this. But in the short term, it's still about the most energy efficient way to run a car with electric power.

Burning straight hydrogen requires modified internal combustion engines. But it can be done. In this case, you are pushing your losses to the production plant, where you will lose energy to the electrolysis of the water. Quite a bit of loss, at the moment. Maybe 30% or worse. A PEM electrolyzer is a lot more efficient, but not ready for prime time. There are likely other efficient ways to do it, but none are in bulk use at the moment. You can also strip hydrogen from natural gas or petroleum, and that, too, is thermally inefficient because you are losing the energy you'd have gotten from combusting the carbons in an engine that burned natural gas. This is also a net producer of CO2, so you can't say you're "green". The other losses are that hydrogen is leaky and you will lose more than you think in pipelines, storage farms and hydrogen gas stations, plus leakage from your tank. Think helium balloon. Off the top of my head, I think the number for THAT loss is about 30%. And you have the usual ICE losses in a combustion engine.

Running hydrogen through fuel cells on a car is not ready for prime time either, fuel cells are cranky and high maintenance, and have roughly the same sorts of wear-out issues you get with batteries.

If you had crazy power and didn't mind wasting it, you could start with water, electrolyze the hydrogens off, add in co2, and reform it into natural gas or diesel-ish oil. But you'd have to have cheap fusion to be able to ignore the losses.

a reply to: Bedlam

I kind of thought that line of questions was heading towards automotive use and possibly the 'HHO' generator illusion of greater efficiency. I had actually wanted to ask what you thought was a good way to phrase an argument against it. I have a relative who swears his 63 Beetle is getting double the mileage or some garbage, and keeps insisting I give him the funds to build one and install it in my vehicle.
I was looking for something that sounded more reasonable than "no, you moron!" Thanks.