StuffThere is stuff that has been found
There is stuff that there is evidence for
There is stuff that explains how things work and so it would be nice if it were real
There is stuff that just makes everything symmetrical so it might be there.
What makes stuff stuff?
So a proton is stuff and a photon is not because a proton has a resting mass and a photon just has energy.
Because E = MC2 and since C, according to Einstein whose equation it is, is the speed of light, a particle of light can have no mass.
ForceIs heat a force? It makes atoms move faster, I think, so that would make it one. For example quarks move in protons - or so they say - and if they do what force is acting on them to make them move? Is there such a thing as independent movement otherwise, what generates the force? Force is what makes things move.
where does electromagnetic force go?So I have a box in the garden. It is made of some opaque material like wood. It is open. I can see inside it. So photons are going in there. I kick it shut and
It is totally dark in there. What happened to the photons.
Well their wave length/frequency can’t alter.
Can their speed? - speed is affected by the medium the wave is travelling through so no
Can their amplitude? Yes as they loose energy the waves will get shallower and shallower and -
Quicker than a flash they flatline and disappear.
Is that possible?
Well, an oxygen atom is stuff and there are loads of them in the box too for the photons to crash into and transfer their energy so yes, it is.
And suddenly the air in the box is slightly warmer.
So, how about an eye?
A black hole
The same - so, how can it get cooler, why doesn’t it get hotter and hotter until it reaches the point - because all the light all the stuff is going in and can’t get out -
But according to Hawking it can - Hawking radiation, so photons can escape so heat can escape so the black hole can cool down before it gets big enough to be too big to cool down
Why doesn’t it heat up again.
Maybe it does and cools down and reheats cos it can’t lose its mass, can it?
Well, yes according to Hawking, in losing heat it loses mass.
Photons now have mass?
So I’m not happy that black holes cool down
Or that they run out of stuff to consume as is suggested in the wiki article on quasars.
I have discovered what quasars are - quasi stellar radio sources. NOT really big stars which is what I thought but the region around a super-massive black hole and the energy, and therefore the light, is caused by mass falling into the accretion disc around the black hole. The gravitational stress and friction just outside the event horizon
22nd February 2013
I started out with
what I accept
A body in motion will continue to move in the same direction unless acted upon.what I question
Energy cannot come out of nothing or go to nothing.
Nothing is faster than the speed of light.a list of questions (click ✔ to go to what I found out)
That because you can make a diagram of it, it must be true.
The universe is expanding.
- what is the mass of light ✔
- is a photon all the colours of the rainbow ✔
- what does light do inside a black hole
- if 2 observers pass each other travelling in exactly opposite directions at3/4 of the speed of light, will they see each other? Will they, looking back at where they would see their backs, see each other as a 'black spot' or not? or what?
- what does 'dark matter' mean
- magnetic field - that word - does it suggest an ether and is the Higgs bosun an attempt to reestablish that there is an ether
- what is the weak force
According to the theory of relativity mass and energy are 2 names for the same thing - mass doesn't change into energy, rest mass becomes a more mobile form of mass. That is why a photon has no mass because it is never at rest.
So what happens to light in a black hole. If it gets squashed more and more will it ever stop and if it does. what will it be?And as I looked for the answers to those - mostly on wikipedia - that started more questions.
Question -what is the mass of light?
The mass of a photon can be calculated theoretically by combining Einstein's E=mc2 and Planck's E=hc/y
m=rest mass (which light does not have so you can't find it experimentally)
c=speed of light in a vacuum (3.0x108 m/sec)
h=Planck's constant (6.626x10-34 Js)
y=the wavelength of light.
so 1 photon of light at a wavelength of 500nm = 4.417x10-36 kg.
Question - is a photon all the colours of a rainbow?
A photon is described by 3 parameters
wave vector determines its wavelength and its direction of propogation
the energy and momentum of a photon depend only on its frequency (or inversely its wavelength)
Visible light is an electromagnetic wave and the frequency of the wave determines its visibility and its colour so a photon is one colour, depending on its frequency.