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1221 Glorious LeaderAbout Mordred
 Currently Viewing Topic: Does a magnetic field have mass?

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No the photons would not accumulate. One thing to realize is that photons are the quantization of the EM field [math]A_\mu[/math] the E and B fields are part of the EM field and are in essence different phase polarizations of the same field. The frequency modes of the EM field in a given volume gives rise to the photon number density (quanta of each field). These frequency modes also degrade or if you prefer disperse through destructive interference. In QED we can calculate the photon number density via the creation and annihilation operators. Though the formulas take time to understand fully you will immediately see the symalarity between the E and B fields. [math]E(r,t)=\frac{i}{2c\sqrt{V}}\sum_k\omega_k[A_k(t)e^{ik\cdot r}A_k^{*}(t)e^{ik\cdot r}][/math] [math]B(r,t)=\frac{i}{2c\sqrt{V}}\sum_k k[A_k(t)e^{ik\cdot r}A_k^{*}(t)e^{ik\cdot r}][/math] now without going into too much detail you should note that only the k for the magnetic field energy and [math]\Omega_k[/math] differ in the two above expressions. The latter is the E field energy though in both cases its proper to square those terms through another formula which I won't get into as some care must be taken with the two independent polarizations E and B of the EM field [math]A_\mu[/math] the main point is that in both cases the photon number density of both the E and B fields are both represented in units of quanta, each unit of quanta is a photon so in your box the number density will depend on the frequency modes given off by the light bulb. ( though you can gain a slightly higher number via temperature which is also part of the EM spectrum.) https://en.wikipedia.org/wiki/Polarization_(waves) see here for the polarization waves of the EM field. Further details see here in terms of EM radiation https://en.m.wikipedia.org/wiki/Electromagnetic_radiation Some of the other equations that will relate to the two I provided are contained here under photon polarizations which is linked to the EM radiation link above. https://en.m.wikipedia.org/wiki/Photon_polarization It will help explain the two above equations.

The point is the time scale to trap light with perfect mirrors is extremely brief. You also seem to think light isn't part of the EM spectrum. Photons are the mediator gauge boson for the EM field this includes mediating the magnetic field though the electric field and magnetic field are one and the same. So if you have a magnetic field you also have photons though offshell.

When was the last time you trapped light without a source? Further more light is part of the EM field.

The solution of the Cosmological constant problem ?
Mordred replied to stephaneww's topic in Speculations
Yes those equations work well. The cosmological constant value can vary a bit depending on dataset. So as long as you have a good approximation your doing good. 
The solution of the Cosmological constant problem ?
Mordred replied to stephaneww's topic in Speculations
No Planck mass isn't a fundamental limit. It's one of the few that isn't. 
The solution of the Cosmological constant problem ?
Mordred replied to stephaneww's topic in Speculations
Planck units are typically extremum values they represent maximum or minimum theoretical bounds. Ie highest or lowest possible limits. 
The solution of the Cosmological constant problem ?
Mordred replied to stephaneww's topic in Speculations
So given that extremely high value would you not say it represents a maximum power. Ie a theoretical maximum much like Planck length is the theoretical minimal observable length ? Ie I would suggest it's value falls into that quoted criteria as being too large for any practical use. 
Mordred started following The solution of the Cosmological constant problem ?

The solution of the Cosmological constant problem ?
Mordred replied to stephaneww's topic in Speculations
Have you calculated the constant value for Planck power? You might want to do that first [math] P_p=\frac{c^5 }{G}[/math] 
The solution of the Cosmological constant problem ?
Mordred replied to stephaneww's topic in Speculations
Fair enough however Planck power has a specific value. It would be interesting to see how you match that value with the cosmological constant. Planck power is one of those units that if it has a practical use it would involve an extreme energy transfer in one Planck time. (There is a reason why that link mentions some of the Planck constants has no practical use.) 
The solution of the Cosmological constant problem ?
Mordred replied to stephaneww's topic in Speculations
This really isn't a very good paper in so far as it doesn't deploy any GR equations in its analysis. Anyways its fine to employ Newton mechanics in terms of spacetime force provided you also realize that the Shell theorem also applies. The paper use of power applies to Dyson luminosity which is a relation velocity to luminosity relations that involves the EM field via Kaluza Klein. An EM field in this instance is coupled to the spacetime metric via a conjecture that all rotating bodies would acquire a magnetic moment thus giving a magnetic moment to velocity power ratio. The theory never really went anywhere you may find occasional studies on it but it's highly hypothetical. It's fundamentally a combination of the EM field to spacetime for stellar bodies so it's localized around those bodies. 
The solution of the Cosmological constant problem ?
Mordred replied to stephaneww's topic in Speculations
Here is another factor to consider Watts=voltage*current. Which doesn't make much sense for Lambda no potential difference. No current. 
The solution of the Cosmological constant problem ?
Mordred replied to stephaneww's topic in Speculations
The thing to keep in mind is unlike say a pressure tank, a battery or a capacitor where energy can be stored and power is transferred at a rate to perform work on some external to the storage device the universe doesn't perform work outside of itself. All the energy is contained within our universe, there is no transfer of heat, energy or mass from outside our universe from inside to outside our universe. Our universe is in essence an isolated system (speaking thermodynamically) an isolated system cannot perform work outside of itself. To put it bluntly in every paper, textbook, article I have ever read on cosmology and the FLRW metric in terms of the universe not once have I ever encountered any usage of power density or even power being involved in any model of the universe I have ever read in 35 years. 
The solution of the Cosmological constant problem ?
Mordred replied to stephaneww's topic in Speculations
I know the following will probably confuse you if you haven't studies thermodynamics but here goes First law of thermodynamics expressed for an adiabatic ( no net inflow or outflow of energy or enthalpy) [math]0=dQ=dU=dU+PdV[/math] Q is total heat assumed to be constant, U is internal energy of matter and radiation in the universe, P is pressure, V is the volume. One finds energy density via [math]u=\frac{U}{V}[/math] and thus [math]du=d(\frac{U}{V})=\frac{dU}{V}U\frac{dV}{V^2}=(p+u)\frac{dV}{V}=3(p+u)\frac{da}{a}[/math] if you divide this equation by [math]d\tau[/math] you get the equations of motion for the FLRW metric [math]u=\rho[/math] now for radiation [math]du=4u\frac{da}{a}[/math] thus u is proportional to [math]a^{4}[/math] for matter [math]du=3\frac{da}{a}[/math] thus u is proportional to [math]a^{3}[/math] now in both these cases as the universe expands the temperature decreases now for the cosmological constant we need to employ a time derivative [math]\dot{u}=3(p+u)\frac{\dot{a}}{a}[/math] now a consequence is that the more negative the pressure becomes the less the energy density decreases as the universe expands however energy is created as the universe expands by Lambda so its pressure is minus its energy density p=u or [math]p=\rho[/math] the total heat is constant in all the above so there is no power in terms of work/time in terms of the FLRW metric power density is never used as there is no transfer of heat outside of our system defined by adiabatic expansion. https://en.wikipedia.org/wiki/Adiabatic_process this gets complicated in terms of reversibility and a further problem of isentropic processes the work must be performed outside our system which doesn't make sense when discussing the universe when our system is the universe volume. There is no outside of the universe for a transfer of work to occur. So how would you define power in this instance ? 
The solution of the Cosmological constant problem ?
Mordred replied to stephaneww's topic in Speculations
From the first link in English As an electromagnetic wave travels through space, energy is transferred from the source to other objects (receivers). The rate of this energy transfer Where is the energy transfer for the cosmological constant ? [math] power=\frac{work}{time}[/math] Start there however it gets more complex thermodynamically. Specifically the first law of thermodynamics. However you might want to start with the distinction between energy density and power density https://energyeducation.ca/encyclopedia/Energy_density_vs_power_density 
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