Few questions about energy

[ithelp]

Hi,
1. What is the maximum frequency of a form of energy observed so far?

2. What is the minimum frequency of a form of energy observed so far ?

3. Given an absolutely 1 cubic meter of empty space, what is the maximum amount of energy that can be stored in that area ?

[GrimJack]

1) Gamma rays - which is kind of of a cop-out as gamma rays are photons with energy greater than 2 * 10^-14 joules (100 keV), SuperNova produce gamma ray bursts of approximately 10^54 ergs. Sorry for skipping around all the different energy units but it is too late and I am getting lazy. Maximum frequency is >3 * 10^19Hz

2) 0 K is the lowest temperature possible and hence the frequency is 0; check out this experiment The NIST team, which includes physicists Anders Kastberg, Steven Rolston, Robert Spreeuw, Poul Jessen and group leader William Phillips, found that atoms became trapped in the valleys of the optical lattice and reached temperatures close to 1 microkelvin. The trapped atoms oscillate back and forth around the bottoms of the valleys. To reduce the temperature of the atoms even more, the scientists reduced the intensity of the light. As the laser light fades, the terrain of the optical lattice becomes less steep, slowing the frequency of the oscillations. This phenomenon, known as adiabatic expansion, drives the atomic temperature even lower, where the typical atomic velocity is only 7 millimeters per second.there are calculators that can translate energy to frequency .

3) I am not sure that the question is posed correctly - if it is pure vacuum then no energy can be stored in it unless you made it into a container then you could pump energy into it but remember E = mC^2 --> m = E/C^2 thus would no longer be a vacuum.

While we are on energy take a look at this analysis of cryptographyOne of the consequences of the second law of thermodynamics is that a certain amount of energy is necessary to represent information. To record a single bit by changing the state of a system requires an amount of energy no less than kT, where T is the absolute temperature of the system and k is the Boltzman constant. (Stick with me; the physics lesson is almost over.)

Given that k = 1.38×10-16 erg/°Kelvin, and that the ambient temperature of the universe is 3.2°Kelvin, an ideal computer running at 3.2°K would consume 4.4×10-16 ergs every time it set or cleared a bit. To run a computer any colder than the cosmic background radiation would require extra energy to run a heat pump.

Now, the annual energy output of our sun is about 1.21×1041 ergs. This is enough to power about 2.7×1056 single bit changes on our ideal computer; enough state changes to put a 187-bit counter through all its values. If we built a Dyson sphere around the sun and captured all its energy for 32 years, without any loss, we could power a computer to count up to 2^192. Of course, it wouldn’t have the energy left over to perform any useful calculations with this counter.

But that’s just one star, and a measly one at that. A typical supernova releases something like 10^51 ergs. (About a hundred times as much energy would be released in the form of neutrinos, but let them go for now.) If all of this energy could be channeled into a single orgy of computation, a 219-bit counter could be cycled through all of its states.
These numbers have nothing to do with the technology of the devices; they are the maximums that thermodynamics will allow. And they strongly imply that brute-force attacks against 256-bit keys will be infeasible until computers are built from something other than matter and occupy something other than space.

[raghavaniyer]

Hi, 1. What is the maximum frequency of a form of energy observed so far?

2. What is the minimum frequency of a form of energy observed so far ?

3. Given an absolutely 1 cubic meter of empty space, what is the maximum amount of energy that can be stored in that area ?

See, it depends on where this 1 cubic meter of space is kept. Assume 1 cubic meter of lead (Pb) @ specific gravity of 11.36, which translates to a mass of 11,350 kg. Keeping it at height of 1 m from the ground produces aPotential Energy of 111.23 KJoules. Dropping it will produce a power of 246.63 KW in about 0.451 seconds.

[ithelp]

1) Gamma rays - which is kind of of a cop-out as gamma rays are photons with energy greater than 2 * 10^-14 joules (100 keV), SuperNova produce gamma ray bursts of approximately 10^54 ergs. Sorry for skipping around all the different energy units but it is too late and I am getting lazy. Maximum frequency is >3 * 10^19Hz

2) 0 K is the lowest temperature possible and hence the frequency is 0; check out this experiment there are calculators that can translate energy to frequency .

3) I am not sure that the question is posed correctly - if it is pure vacuum then no energy can be stored in it unless you made it into a container then you could pump energy into it but remember E = mC^2 --> m = E/C^2 thus would no longer be a vacuum.

While we are on energy take a look at this analysis of cryptography

Thanks for such a detailed reply. Any idea whether any form of energy exits which does not interact with matter at all ?

[Agilemind]

Thanks for such a detailed reply. Any idea whether any form of energy exits which does not interact with matter at all ?

Yes there is, it's called Dark Energy it has been determined to exists theoretically and is supposed to cause the universe to expand. As far as we know it doesn't interact directly with matter at all (so no-one has observed it).

[GrimJack]

See, it depends on where this 1 cubic meter of space is kept. Assume 1 cubic meter of lead (Pb) @ specific gravity of 11.36, which translates to a mass of 11,350 kg. Keeping it at height of 1 m from the ground produces a Potential Energy of 111.23 KJoules. Dropping it will produce a power of 246.63 KW in about 0.451 seconds.

No it does not depend on where this cubic meter of empty space is kept - a cubic meter of empty space can not be a cubic meter of lead by definition.

[GrimJack]

Thanks for such a detailed reply. Any idea whether any form of energy exits which does not interact with matter at all ?

The easy answer is a neutrino - only one in a trillion passing through the center of the earth would actually be affected by it; about 60 billion solar neutrinos pass through every square centimeter of the Earth's surface every second. A neutrino is not mass-less but has so little mass that it can approach the speed of light.

a 'normal' unit of energy produced at the center of the sun takes about a million years to reach the surface of the sun whereas a neutrino produced at the center of the sun will reach the earth in about 8 minutes

Do you want to be really confused? Check this out - a new paper posits a universe where time and space are interchangeable via a constant in the same way E = mC^2 makes mass and energy interchangeable. This implies that Dark Energy makes up makes up 75% of the total mass/energy of the universe. But this flies in the face of the cosmic background radiation that is theoretically the energy left over from the Big Bang.

In other news, the number of angels dancing on the head of pin is up 32% but I digress.

[raghavaniyer]

The easy answer is a neutrino - only one in a trillion passing through the center of the earth would actually be affected by it; about 60 billion solar neutrinos pass through every square centimeter of the Earth's surface every second. A neutrino is not mass-less but has so little mass that it can approach the speed of light.

a 'normal' unit of energy produced at the center of the sun takes about a million years to reach the surface of the sun whereas a neutrino produced at the center of the sun will reach the earth in about 8 minutes

Do you want to be really confused? Check this out - a new paper posits a universe where time and space are interchangeable via a constant in the same way E = mC^2 makes mass and energy interchangeable. This implies that Dark Energy makes up makes up 75% of the total mass/energy of the universe. But this flies in the face of the cosmic background radiation that is theoretically the energy left over from the Big Bang.

In other news, the number of angels dancing on the head of pin is up 32% but I digress.

Is there any material that reacts to a neutrino bombardment? What would be the avearge density of flow of neutrinos per square meter?

[GrimJack]

The mean free path of a neutrino is about a light year of lead (a light second is 186,000 miles); in actuality, a moderate(!?) energy neutrino could easily pass through a thousand light years of lead.

The reason we can record neutrino activity at all is because 6 trillion neutrinos pass through a given square meter per second so in a given week a certain number of neutrinos will hit a detector just because there are so effing many of them are flying around. The estimates given are only for neutrinos produced in the heart of our sun; generally speaking, all the suns in the universe are producing an equivalent amount. It is really comforting that we are essentially empty space - otherwise we would be ripped to pieces by neutrinos.

[ithelp]

Last question , I was trying to understand little bit of big bang , they said huge energy came from somewhere in a very small unit of absolutely empty space , can I not heat 1 cubic meter of absolutely empty space ? if not can I not fill the 1 cubic meter empty space with lot of mass less energy particles.

Again my knowledge of physics is elementary.

[GrimJack]

Here is the trick - as long as the energy total = zero, anything is possible.

Every particle has it's anti-particle and so any given volume of empty space can suddenly be filled with particles then empty again. Then remember that matter and energy is interchangeable so it might not be possible to fill the space with mass-less energy particles. It was once thought that neutrinos were mass-less.

consider that every particle has its anti-particle - let's use the proton in this thought experiment - then consider that the anti-proton can be considered a proton moving backwards in time. It has been posited that all the protons in the universe are actually the same one moving back and forth in time. Unfortunately for this thought experiment, quarks don't quite work that way.

Please don't stop asking questions - I have to learn something in order to answer them (er, did I actually answer your question?).

[Agilemind]

Empty space cannot be heated because temperature is a measure of the movement of particles (usually molecules) it you have no particles by definition you have not temperature so you cannot heat it -> this is why vacuum windows (two panes separated by near vacuum) are the best insulation.

Also E=mc^2 states that mass and energy are interchangeable: energy is mass, and mass is energy. So mass-less energy particles is a contradiction.

The very beginning of the big bang is not understood because all the mathematical equations blow up (go to infinity) as they approach 0 time.
for a simple example consider f(x) = 1/x, you can find a value and thus understand the function as close to x = 0 as you want but at exactly x = 0 it ceases to make sense.

There is Brane theory that proposes our universe exists on one of many membranes (branes) and that the Big Bang is the result of a collision between our brane and a neighbouring brane.

[raghavaniyer]

Last question , I was trying to understand little bit of big bang , they said huge energy came from somewhere in a very small unit of absolutely empty space , can I not heat 1 cubic meter of absolutely empty space ? if not can I not fill the 1 cubic meter empty space with lot of mass less energy particles.

Again my knowledge of physics is elementary.

I recall our discussion about E=m*c^2 and dark energy. can relativity theory be applied to dark energy? If does the dark energy react with other energies? Is there an energy that does not react with matter? Sorry for asking too many questions.

[ithelp]

Energy is vibration , which creates ripple across the medium it passes through , so is dark energy something opposite to energy which can cancel the vibration , like I throw a stone in a river , a ripple is created , now is dark energy something which can nullify the ripple in no time ?
Is energy also a dimension which is not understood by us?

[Agilemind]

Energy is vibration , which creates ripple across the medium it passes through , so is dark energy something opposite to energy which can cancel the vibration , like I throw a stone in a river , a ripple is created , now is dark energy something which can nullify the ripple in no time ? Is energy also a dimension which is not understood by us?

Energy isn't just a vibration otherwise we would still believe space is filled with an ether that vibrates as light passes through it. Dark energy is not the opposite to energy it is basically filling a hole in physics equations, we don't know what it is where it comes from or what is really does. So far it has been used to try to explain the continued acceleration of the expansion of the universe and to fill the missing 74% of the matter-energy in the universe. Just as Dark Matter is used to fill the missing 22% of the missing matter-energy in the universe and to explain the extra gravity needed to hold galaxies together and the gravity lensing of some starlight as we've observed.

Energy isn't usually thought of as a dimension but as the 'stuff' that exists in the dimensions of the universe.

[raghavaniyer]

Here is the trick - as long as the energy total = zero, anything is possible.

Every particle has it's anti-particle and so any given volume of empty space can suddenly be filled with particles then empty again. Then remember that matter and energy is interchangeable so it might not be possible to fill the space with mass-less energy particles. It was once thought that neutrinos were mass-less.

consider that every particle has its anti-particle - let's use the proton in this thought experiment - then consider that the anti-proton can be considered a proton moving backwards in time. It has been posited that all the protons in the universe are actually the same one moving back and forth in time. Unfortunately for this thought experiment, quarks don't quite work that way.

Please don't stop asking questions - I have to learn something in order to answer them (er, did I actually answer your question?).

you did answer my questions. Is there any experiment on dark energy? something like Joule's friction Cone apparatus, or Carnot's engine?

[Agilemind]

you did answer my questions. Is there any experiment on dark energy? something like Joule's friction Cone apparatus, or Carnot's engine?

As far as I know not yet. Because it is such a new idea there are still lots of people investigating so hopefully soon (next decade or two) there will be experimental or better observational evidence for Dark Energy.

[AuburnMathTutor]

Again, call me a sceptic but it's hard to believe in this kind of stuff. It is a little too reminiscent of the luminiferous aether theory for my comfort, despite the various "smoking guns" for its existence. While there certainly seem to be some predictions that are confirmed, let us not forget that there are predictions which the luminiferous aether theory leads to which can be verified by experiment.

Part of me thinks that scientists have become a lot better at making hypotheses seem true than they were at the turn of the last century. Who knows, maybe there is dark matter/energy. Beats me. A theory can be a useful tool for understanding nature without actually being *true* in the absolute sense of the word. We still think of electricity in circuits as fluid and still indicate the direction as though positive stuff is flowing.

[Agilemind]

Again, call me a sceptic but it's hard to believe in this kind of stuff. It is a little too reminiscent of the luminiferous aether theory for my comfort, despite the various "smoking guns" for its existence. While there certainly seem to be some predictions that are confirmed, let us not forget that there are predictions which the luminiferous aether theory leads to which can be verified by experiment.

Part of me thinks that scientists have become a lot better at making hypotheses seem true than they were at the turn of the last century. Who knows, maybe there is dark matter/energy. Beats me. A theory can be a useful tool for understanding nature without actually being *true* in the absolute sense of the word. We still think of electricity in circuits as fluid and still indicate the direction as though positive stuff is flowing.

I agree (at least when it comes to theoretical physics). One of my favourite quotes is that "if you think you understand quantum theory, you haven't a clue" (or something like that). Part of me thinks when they finally do find the Unified Theory (the theory that will bring gravity and quantum theory together) it will end up being much simpler and completely different than either of them and will actually make sense.

[GrimJack]

I agree (at least when it comes to theoretical physics). One of my favourite quotes is that "if you think you understand quantum theory, you haven't a clue" (or something like that). Part of me thinks when they finally do find the Unified Theory (the theory that will bring gravity and quantum theory together) it will end up being much simpler and completely different than either of them and will actually make sense.

Richard Feynman made that observation at a time when physics was in turmoil, starting with the Michelson–Morley experiment (they were trying to find the direction/current of the aether wind), progressed through Einstein's Relativity (he was trying to find the theory of absolutes) up through the 'explosion' of particles and on past. I am not saying I understand quantum theory or that very many people do but the paradigm has shifted and what was unimaginable to the leading edge of science has pervaded society (think 'quantum', 'Schrodinger's Cat', 'wavicle').

My favorite Feynman story (yes, I am going to repeat it here) is about how he worked with other physicists, they would sit around and discuss results and various particle interactions. When they were stumped, Richard would disappear for a couple minutes to a couple hours then return with the answer. He never came up with the answer during the bull sessions and this began to perturb his co-workers - eventually, after bringing up a particularly complex particle interaction and Feynman left per usual, they burst into his office and there he was with a bunch of diagrams. He was so embarrassed because he could not keep all the interactions in his head so he cheated and diagrammed the interactions. These diagrams (and the definitions/language used to read them) are still used today.

but I digress