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Physics, Astronomy & Cosmology / Re: ESSENTIAL MAINTENANCE
« on: Yesterday at 19:44:51 »
If not are the consequences that my account starts posting clickbait and advertising?
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With a stationery packed train stuck in tunnel, what are the chances of oxygen deprivation ?Office stationery doesn't consume oxygen, and whilst time spent packed in the stationery cupboard can be fun, I don't recall our hyperventilation being primarily caused by excess CO2.
My word, there were days it was soooo packed it was a joke.
People really enjoying their commute last Tuesday. see how they smile ?The foreground guy suspects that Ophelia there is doing something inappropriate, yet the offending grope origin actually is from the smiling guy just beyond him.
With a stationery packed train stuck in tunnel, what are the chances of oxygen deprivation ?The tube, like any tunnel, is supposed to have continuous ventilation to deal with anything not moving, and also to carry away exhaust fumes. Not too much the latter in an electric subway, but think of the old days of steam trains going through long tunnels, windows shut due to the smoke of the engine. Tunnels could only get so long back then.
If the E-coli in faeces is harmful when introduced in the mouth, how did it get there in the first place?Through the mouth. Like most harmful materials it?s a question of dosage and if you only ingest a small amount your body can cope, but it will still grow in the gut and be concentrated in the faeces to infect someone else.
Why Does Light NOT Experience Time?On a sidenote... I heard an interesting podcast from Sean Carrol on "Does Time Exist?" (2 hours).
the ordinary Schrodinger equation says Hamiltonian acting on quantum state is the time derivative of the quantum state.Sean Carrol does not resolve this apparent contradiction in the podcast; it is a paradox of modern physics.
The Wheeler-DeWitt equation says, Hamiltonian acting on the quantum state equal zero. So, there is no time variable in the Wheeler-DeWitt equation. ... So, time has disappeared
So, I found out that light does NOT experience time because of it's speedMore precisely, the speed of c relative to any object does not represent a valid inertial frame where things like distance, time, or experience are meaningful concepts. One can freely change inertial frames and back using the Lorentz transformation, but no transformation exists to such a frame. So they put the light in a medium and then we have a valid frame relative to which the light makes no progress against the fast moving medium. That seems to be what these guys are doing.
So, I then presumed that if it slows down then it should experience time...but apparently not !!! what's that all about ?Time can be experienced in such a frame, so the only thing stopping it is the same thing that stops a rock from experiencing it: Lack of googley eyes. Point is, one can say put a human in the frame next to it and have a pet Tonoski waiting stationary next to him. Best not to watch him because any light going to the side that you can see is light permanently gone from it. It will fade quickly if defecting its very essence at that rate.
Why Does Light NOT Experience Time When It Slows Down ?Who says it doesn't? I mean, it's a light pulse in a valid frame. OK, a photon can't do it because it gets absorbed before it can be slowed by some interaction with the medium.
'Light' does NOT rhyme with 'Cabbage'No, but it front-end rhymes with lituce.
Sun rhymes with 'bum' lol chortle..snigger...guffaw !!Oh no it don't, Mary Poppins.
Now we all know that Photons take's approx 100,000 years to escape the Sun.And neutrinos thus generated take about 2.5 seconds to do the same thing.
Does that mean that after Fusion commenced ..... the Sun did not shine for 100,000 years ?That's the interesting question. The sun was not as big and was not so defined back when fusion commenced. It was already hot just from all that mass falling into that gravity well, so it already shone at that point, but a dull infra-red radiation of heat, not proper fusion light. That light did just suddenly blink on, so there's no clear beginning of it and no clear point where special kind of light began to hit the surface.
Sun rhymes with 'bum' lol chortle..snigger...guffaw !!No it doesn't, any more than do the lines "Glory streams from heaven afar; Heavenly hosts sing haleluyar" (OK, but that was a rhyme stolen from "Blazing saddles").
When galaxies collide, their central supermassive black holes (SMBHs) should also eventually merge.The quote you give kind of says it. To get closer, their kinetic energy must go somewhere, else, like Earth, it just keeps orbiting the sun without getting closer.
However, as the SMBHs approach each other within about a parsec (3.26 light-years), the density of stars and gas in the galactic core becomes too low to effectively remove the energy and momentum needed for the final plunge and merger.
This "energy loss problem" prevents the black holes from spiraling inward and merging within a reasonable timeframe.
So how do Black Holes merge then ?
Maybe in the future, our descendants will be able to harness the power of this motion to make a perpetual machine ?Only if they repeal the most fundamental laws of physics and common sense. But I wouldn't put that past Donald Trump and the US Supreme Court..