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NJV

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Since I've given up studying at the university, I've had no public lessons on physics, yet my questions about physics have been accumulating ever since, as I still sometimes try to study individually. With the Internet, most notably Wikipedia, as my prime source of information, I sometimes hardly manage to learn anything new at all - especially when I search information about quantum mechanics, the formulae of which have often boggled my mind. Having graduated from secondary education only as of December 2007, I have no considerable physical knowledge - please forgive me if some of my questions will be simplistic.

I've asked for several private teachers to answer my questions, but they either did not have the patience or could not. The list is pretty long, but if some aficionado could help me with some of my questions, I'd greatly appreciate it.

———

Astrophysics

Why is the surface gravity of a Schwarzschild black hole 1/4M? Shouldn’t this be

g = Gm/r2

= Gm/(2Gm/c2)2

= c4/4GM?

———

What is the total thermal energy of the sun?

———

What is the average temperature and velocity of the sun’s particles?

———

Why is the corona of the sun a million kelvins?

———

What is the distance of the event horizon from the black hole?

———

What is the radius of the ergosphere?

———

What is the semi-major axis of the photon sphere(s)?

———

How can one know the total energy received by a moon from the magnetosphere of a planet?

———

The scale factor is defined as

a(t) = L/?

where “L is the physical distance, ? is the distance in comoving units.” What does this mean?

———

What is the rate at which the sun converts kinetic energy (heat) into heat?

———

How can the energy of dark energy be proportional to volume?———

Why is the surface temperature of the sun so low?

———

What is the total heat of the universe?

———

What is the chance of occurrence of the Big Bang (per unit of space and time)?

———

When do black holes explode?

Electrodynamics

What causes resistance?

———

Paramagnetic materials are attracted by fields because of the presence of unpaired electrons, while for diamagnetic materials it’s just the opposite. Why is this?

———

Why are Maxwell’s equations so significant?

———

How can the electrical current density of a material be known based only upon the its properties?

———

What is the current density of copper?

———

How does a ferroelectric tunnel junction lead to giant electroresistance, and what it its use?

———

What is the Josephson effect?

———

What is cationic lightning?

———

In a ferromagnetic, electrons with the same spin sometimes form pairs. How are these pairs called?

———

What explains the Ochsenfeld-Meissner effect?

Forces

What is the mathematical relation between the speed and strength of a force?

Mechanics

What is the virial theorem?

———

What is the derivation of the formula of gravitational binding energy (E = ? GM2/r)?

———

What is the mathematical relation between the density of particles of a mass, and the heat that will be produced when its movement is inverted?

———

On what, chemically, depends the stress a substance can bear?

———

For a standing wave, y(z,t) = A(z,t) sin (kz - ?t + ?). How is this applied?

———

The speed of sound can be calculated using formula

c = ?(K/?)

Thus, for water, c = ?(2,2 · 109 Pa) ? 50 km/s.

———

If two spheres graze, how can the exchange of momentum be known?

———

What is the work required to compress a mass?

———

What is Langrangian mechanics?

———

Why is the gravitational binding energy equal to ? GM2/r?

Hydrodynamics

If the gravitational acceleration and surface pressure and surface density of a planet’s atmosphere are given, how can the mass of the entire atmosphere be known? Obviously, the problem here is that the atmosphere tapers gradually.

Relativity

How is the stress-energy tensor used?

———

What is a spin tensor?

———

What is a Poincaré group?

———

What is Terrel rotation?

———

Does charge experience a Lorentz effect like mass does?

———

Why is the speed of light 299.792.458 meters per second?

Is this because of the relation ?0µ0 = 1/c2?

———

What would be the maximum length contraction matter could endure before disintegrating?

———

What is the radius for Kerr black holes, Reissner-Nordström black holes and Kerr-Newman black holes?

———

The energy provided by a propellant is:

Enet = m0c2(? - ½?ß2)

The derivative of this to the speed is:

Enet’(v) = p(? - ½ß2?) - Ek/2 [(2ß?/c - ½ ß2(1-ß2)–½]/?2

Then what is the maximum energy a propellant can provide (what are the zeroes of the derivative)?

Thermodynamics

If you pour water on a hot plate, it will form drops as it evaporates. Why is this? Does the plate’s temperature reduce the adhesion of water to the plate, or does it cause it to float briefly?

———

If at one point in a space the temperature rises, what will be the heat rate per volume?

———

If the thermal diffusivity and heat are known, what is the thermal diffusion?

———

Upon discharge of greenhouse gases, the atmosphere is heated immediately. But the heat takes time to permeate the oceans and the soil. As the warming caused by greenhouse gases will pervade the planet, the atmosphere will gradually become cooler. Then how will the global warming of the atmosphere alone evolve if the radiative forcing is known?

———

What explains of the Nernst heat theorem?

———

According to kinetic theory,

P = ??v2

Thus,

F/A = ?mv2/V

? ma/A = ?mv2/V

? (v/t) V = ?v2 A

? V/A = ?s

? r = s

But the work performed by pressure is PV!

———

For the energy of heat,

Q = cm?T

where c, the specific heat capacity satisfies the formula

c = T/N (?S/?T).

Thus, it is temperature-dependent. How can this formula be used if the increase in temperature is very high?

———

H = U + PV

= Q + W + PV

How can W differ from both PV and Q?

Nuclear physics

How can the energy produced in nuclear fusion / fission be calculated?

Quantum mechanics - QM

According to the De Broglie equation, Ek = mc2(?-1)/h. How can this be correct?

———

How is the position vector used?

———

If we combine the formulae I(h,v) = (2hv3/c2) (1/(ehv/kT - 1)) and E = hv/1/ehv/kT - 1), we get that the spectral radiance satisfies the formula:

I = ½E?2 = ½hc? = ½ mc2?2

———

What is perturbation theory?

———

According to this site (http://library.thinkquest.org/C007571/english/advance/english.htm), the lifetime of a virtual photon is 1/8?f, which would follow from the Heisenberg principle: the lifetime of a virtual particle-antiparticle pair would be equal to the uncertainty of a particle with that energy. Why is this so?

———

For two carbon atoms with double bonds, what is the electrostatic repulsion if they approach each other in phonon-heat transfer?

———

What causes tachyon condensation?

———

What causes the Higgs mechanism?

———

What is the gauge field tensor?

———

How are the Hawking radiation equations derived? Why is

t = 5120?G2M3/?c4

where t is the evaporation time? More importantly, how can

P = ?c6/15360?G2M2?

If we invert t, we get:

1/t =?c4/5120?G2M3

Now, t is the time in which the total energy of the black hole, Mc2, is evaporated, so that:

P =?c6/5120?G2M2

Why is this three times greater? How can three times the black hole’s mass be converted? Is two thirds of this energy produced by the vacuum fluctuations that cause it?

———

Photons travel according to the spin of a black hole in the inner photon sphere, but not according its spin in the outer photon sphere. Why?

———

How are quantum states calculated?

———

How is the bra-ket notation used?

———

What causes emission of gravitons?

———

How are virtual photons be responsible for electromagnetism?

———

What is Hartree’s energy?

———

Can the lifetime of an elementary particle be calculated based on its properties?

———

According to the equation E = mc2, all energy is contained within mass. Yet, charge also has energy. Charge is not a subset of mass, however - that is, it does not increase mass; conversely, it appears to decrease it, as the difference in mass between protons and neutrons shows.

———

What causes spin-spin interactions?

———

What is the bra-ket notation for?

———

According to Wikipedia, “a dyon is a hypothetical particle with both electric and magnetic charges.” What is the difference between electric and magnetic charges? Doesn’t a particle with electric charge automatically have magnetic charge as well? Isn’t that why it’s called “electromagnetism?”

———

What are polarons?

———

What are Goldstone bosons?

———

What are polaritons?

———

Is there a formula of the strength of the strong and weak forces as there is for electromagnetism and gravity?

———

How are zero-currents of Z particles involved in the weak force?

———

Why is the Planck temperature the upper limit to temperature? A particle with the Planck energy wouldn’t become a black hole - a particle with ?(?) times that energy would!

———

According to Wikipedia (http://en.wikipedia.org/wiki/Orders_of_magnitude_(energy)) the Planck energy is the energy at which the four fundamental forces become equal in strength. What does this mean? In function of what variables?

———

What explains the Bell theorem? Why will “Bob and Alice” get the same results 100% of the time when they are measured at an angle of 180° and different results 100% of the time when they are measured at an angle of 90°?

———

What explains the behavior of Einstein-Bose condensates and Fermionic condensates?

———

What causes superfluidity?

———

What is superselection?

———

What is the diameter of a photon?

———

In the Wikipedia article of the finite potential barrier, they keep using the term “barrier height” without explaining it. What is it?

———

What is the delta potential barrier?

———

As they are deflected by other charges, photons must essentially have charge. What is the charge of a photon, then?

———

What is the rate of emission of virtual photons from a charge?

———

The number of electrons per shell equals 2n^2. Is there such formula for nucleonic shells?

———

How did the Dirac equation lead to the discovery of the positron?

I've asked for several private teachers to answer my questions, but they either did not have the patience or could not. The list is pretty long, but if some aficionado could help me with some of my questions, I'd greatly appreciate it.

———

Astrophysics

Why is the surface gravity of a Schwarzschild black hole 1/4M? Shouldn’t this be

g = Gm/r2

= Gm/(2Gm/c2)2

= c4/4GM?

———

What is the total thermal energy of the sun?

———

What is the average temperature and velocity of the sun’s particles?

———

Why is the corona of the sun a million kelvins?

———

What is the distance of the event horizon from the black hole?

———

What is the radius of the ergosphere?

———

What is the semi-major axis of the photon sphere(s)?

———

How can one know the total energy received by a moon from the magnetosphere of a planet?

———

The scale factor is defined as

a(t) = L/?

where “L is the physical distance, ? is the distance in comoving units.” What does this mean?

———

What is the rate at which the sun converts kinetic energy (heat) into heat?

———

How can the energy of dark energy be proportional to volume?———

Why is the surface temperature of the sun so low?

———

What is the total heat of the universe?

———

What is the chance of occurrence of the Big Bang (per unit of space and time)?

———

When do black holes explode?

Electrodynamics

What causes resistance?

———

Paramagnetic materials are attracted by fields because of the presence of unpaired electrons, while for diamagnetic materials it’s just the opposite. Why is this?

———

Why are Maxwell’s equations so significant?

———

How can the electrical current density of a material be known based only upon the its properties?

———

What is the current density of copper?

———

How does a ferroelectric tunnel junction lead to giant electroresistance, and what it its use?

———

What is the Josephson effect?

———

What is cationic lightning?

———

In a ferromagnetic, electrons with the same spin sometimes form pairs. How are these pairs called?

———

What explains the Ochsenfeld-Meissner effect?

Forces

What is the mathematical relation between the speed and strength of a force?

Mechanics

What is the virial theorem?

———

What is the derivation of the formula of gravitational binding energy (E = ? GM2/r)?

———

What is the mathematical relation between the density of particles of a mass, and the heat that will be produced when its movement is inverted?

———

On what, chemically, depends the stress a substance can bear?

———

For a standing wave, y(z,t) = A(z,t) sin (kz - ?t + ?). How is this applied?

———

The speed of sound can be calculated using formula

c = ?(K/?)

Thus, for water, c = ?(2,2 · 109 Pa) ? 50 km/s.

———

If two spheres graze, how can the exchange of momentum be known?

———

What is the work required to compress a mass?

———

What is Langrangian mechanics?

———

Why is the gravitational binding energy equal to ? GM2/r?

Hydrodynamics

If the gravitational acceleration and surface pressure and surface density of a planet’s atmosphere are given, how can the mass of the entire atmosphere be known? Obviously, the problem here is that the atmosphere tapers gradually.

Relativity

How is the stress-energy tensor used?

———

What is a spin tensor?

———

What is a Poincaré group?

———

What is Terrel rotation?

———

Does charge experience a Lorentz effect like mass does?

———

Why is the speed of light 299.792.458 meters per second?

Is this because of the relation ?0µ0 = 1/c2?

———

What would be the maximum length contraction matter could endure before disintegrating?

———

What is the radius for Kerr black holes, Reissner-Nordström black holes and Kerr-Newman black holes?

———

The energy provided by a propellant is:

Enet = m0c2(? - ½?ß2)

The derivative of this to the speed is:

Enet’(v) = p(? - ½ß2?) - Ek/2 [(2ß?/c - ½ ß2(1-ß2)–½]/?2

Then what is the maximum energy a propellant can provide (what are the zeroes of the derivative)?

Thermodynamics

If you pour water on a hot plate, it will form drops as it evaporates. Why is this? Does the plate’s temperature reduce the adhesion of water to the plate, or does it cause it to float briefly?

———

If at one point in a space the temperature rises, what will be the heat rate per volume?

———

If the thermal diffusivity and heat are known, what is the thermal diffusion?

———

Upon discharge of greenhouse gases, the atmosphere is heated immediately. But the heat takes time to permeate the oceans and the soil. As the warming caused by greenhouse gases will pervade the planet, the atmosphere will gradually become cooler. Then how will the global warming of the atmosphere alone evolve if the radiative forcing is known?

———

What explains of the Nernst heat theorem?

———

According to kinetic theory,

P = ??v2

Thus,

F/A = ?mv2/V

? ma/A = ?mv2/V

? (v/t) V = ?v2 A

? V/A = ?s

? r = s

But the work performed by pressure is PV!

———

For the energy of heat,

Q = cm?T

where c, the specific heat capacity satisfies the formula

c = T/N (?S/?T).

Thus, it is temperature-dependent. How can this formula be used if the increase in temperature is very high?

———

H = U + PV

= Q + W + PV

How can W differ from both PV and Q?

Nuclear physics

How can the energy produced in nuclear fusion / fission be calculated?

Quantum mechanics - QM

According to the De Broglie equation, Ek = mc2(?-1)/h. How can this be correct?

———

How is the position vector used?

———

If we combine the formulae I(h,v) = (2hv3/c2) (1/(ehv/kT - 1)) and E = hv/1/ehv/kT - 1), we get that the spectral radiance satisfies the formula:

I = ½E?2 = ½hc? = ½ mc2?2

———

What is perturbation theory?

———

According to this site (http://library.thinkquest.org/C007571/english/advance/english.htm), the lifetime of a virtual photon is 1/8?f, which would follow from the Heisenberg principle: the lifetime of a virtual particle-antiparticle pair would be equal to the uncertainty of a particle with that energy. Why is this so?

———

For two carbon atoms with double bonds, what is the electrostatic repulsion if they approach each other in phonon-heat transfer?

———

What causes tachyon condensation?

———

What causes the Higgs mechanism?

———

What is the gauge field tensor?

———

How are the Hawking radiation equations derived? Why is

t = 5120?G2M3/?c4

where t is the evaporation time? More importantly, how can

P = ?c6/15360?G2M2?

If we invert t, we get:

1/t =?c4/5120?G2M3

Now, t is the time in which the total energy of the black hole, Mc2, is evaporated, so that:

P =?c6/5120?G2M2

Why is this three times greater? How can three times the black hole’s mass be converted? Is two thirds of this energy produced by the vacuum fluctuations that cause it?

———

Photons travel according to the spin of a black hole in the inner photon sphere, but not according its spin in the outer photon sphere. Why?

———

How are quantum states calculated?

———

How is the bra-ket notation used?

———

What causes emission of gravitons?

———

How are virtual photons be responsible for electromagnetism?

———

What is Hartree’s energy?

———

Can the lifetime of an elementary particle be calculated based on its properties?

———

According to the equation E = mc2, all energy is contained within mass. Yet, charge also has energy. Charge is not a subset of mass, however - that is, it does not increase mass; conversely, it appears to decrease it, as the difference in mass between protons and neutrons shows.

———

What causes spin-spin interactions?

———

What is the bra-ket notation for?

———

According to Wikipedia, “a dyon is a hypothetical particle with both electric and magnetic charges.” What is the difference between electric and magnetic charges? Doesn’t a particle with electric charge automatically have magnetic charge as well? Isn’t that why it’s called “electromagnetism?”

———

What are polarons?

———

What are Goldstone bosons?

———

What are polaritons?

———

Is there a formula of the strength of the strong and weak forces as there is for electromagnetism and gravity?

———

How are zero-currents of Z particles involved in the weak force?

———

Why is the Planck temperature the upper limit to temperature? A particle with the Planck energy wouldn’t become a black hole - a particle with ?(?) times that energy would!

———

According to Wikipedia (http://en.wikipedia.org/wiki/Orders_of_magnitude_(energy)) the Planck energy is the energy at which the four fundamental forces become equal in strength. What does this mean? In function of what variables?

———

What explains the Bell theorem? Why will “Bob and Alice” get the same results 100% of the time when they are measured at an angle of 180° and different results 100% of the time when they are measured at an angle of 90°?

———

What explains the behavior of Einstein-Bose condensates and Fermionic condensates?

———

What causes superfluidity?

———

What is superselection?

———

What is the diameter of a photon?

———

In the Wikipedia article of the finite potential barrier, they keep using the term “barrier height” without explaining it. What is it?

———

What is the delta potential barrier?

———

As they are deflected by other charges, photons must essentially have charge. What is the charge of a photon, then?

———

What is the rate of emission of virtual photons from a charge?

———

The number of electrons per shell equals 2n^2. Is there such formula for nucleonic shells?

———

How did the Dirac equation lead to the discovery of the positron?

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