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Post by silverdragon on Apr 17, 2016 11:57:01 GMT
Light travelling backwards.
Keep in mind that Einsteins law of relevance in that its where you are standing that matters....
This seems to be a suitable place to put this idea, because I can not find anywhere at all that answers this other than "maybe", so, its maybe a theory, maybe its answerable, maybe its not.
First we have to define the centre of the Universe as we know it.
There has been many theories that state that as the universe expanded from one single point at a very fast speed, "everywhere" is therefore the centre of the universe, lets not get into that, lets look at the expanding bubble of universe that we know, and define a point that everything else is generally moving "away" from, and make the decision that that is where we will define for the point of this discussion is good enough to say was the start point and is for all that can be argued more or less the centre of the universe?... the point of origin.
Right.
So in that initial huge explosion, the mother of all big bangs that we know of, everything first moved away at one hell of a speed, and, in fact, accepted as faster than the speed of light.
In so much as I cant find anyone who would disagree that being there WAS enough power in that explosion that faster than light travel was instantaneously possible.....
So being that there isnt any friction and a body in motion stays in motion....
At the extreme edge of the universe we must still have matter that is spreading out faster than the speed of light, and therefore, is "Going away" from the observers point of view at the centre of the universe faster than light speed.
You can all see where this is going?.. good.
Because its therefore logical that we who are forever bound by the laws of physics, must therefore now accept, that, we cant bloody see those bodies flying away because the light from them will NEVER reach us?.
So, in question, how fast are "we" going?...
I use that because its well known that they actually fact checked that at the time of writing it.
So, may I then suggest that we can see more of the universe in the general direction of which WE are travelling and less of the other side that has always been travelling away from the point of origin.
But even still, if latter at the very edge of the universe is still travelling away at faster than light speed, until we catch up with it, we aint goina see it, and even then, light has mass, so, if that mass is also travelling in the general direction of "away", given from the point of view of an observer at the point of origin centre of the universe or any body that is less that light speed travelling away from that point of origin "behind" those bodies, the light from those faster than light speed bodies is generally travelling away from us as well, so from the observers point, light is travelling in the wrong direction, "away" from the observer...?....
Am I making any sense on this one?.
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Post by mrfatso on Apr 17, 2016 20:53:05 GMT
This might be of interest to you. en.m.wikipedia.org/wiki/Observable_universeIn astronomy and cosmology they have a concept Calle ether observer able universe, we are only able to see the universe were the light has had enough time to travel to us. Were in the expansion phase of the formation of the universe the fabric of space time itself grew so fast it was faster than the speed of light, some of the universe we cannot see as the light from those parts has not had enough time to reach us yet. However the expansion phase did not last forever, and it seems that the fabric of space times did not continue to travel at that speed for ever, there we get into questions of multiple universes and other cosmological theories, our universe is not the only one and exists in something that we cannot perceive. but it is interact with that greater structure which slowed the expansion phase if those theories are correct. |
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Post by the light works on Apr 17, 2016 23:54:14 GMT
so more along the lines of relative speeds than actually going backwards. I was wondering how one would tell - if photons have taillights or something.
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Post by silverdragon on Apr 18, 2016 6:00:36 GMT
From MrF's link, and no I didnt look at Wiki before I wrote my post, but that seems to argue the same point I was asking.
Therefore, maybe I aint the first 'smart cookie' in the jar to ask this bloody awkward question, how do we know what we cant see.
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Post by OziRiS on Apr 23, 2016 0:22:21 GMT
Strange I didn't catch this earlier...
I've argued pretty much the same point against the idea that "there's no center of the universe".
It stands to perfect logic that anything that started somewhere ends somewhere and if there are ends, there must also be a middle. However, due to the continued expansion of the universe, there are parts we can't see. Who says we aren't just moving exactly fast enough that it appears to us that we're in the middle of a sphere, even though we're actually halfway between the middle and the edge? Hell, expansion might even be moving us along fast enough that we can't even see the middle of the universe anymore!
Our best estimate right now (or at least the last time I checked) is that the universe is about 90 billion light years across. Okay, but how do we know that? If anything beyond that 90 billion light year border is moving faster than the speed of light relative to us, then we'll never even know it exists. There might be double the amount of universe in one direction we look and eight times as much universe in the opposite direction for all we know.
Let's just play with those numbers for a moment. Let's say we only see a tenth of what's actually there. Look in one direction and there's actually another 90 billion light years beyond it before you hit the true edge of the universe. Look in the other direction and there's 720 billion light years more. 900 billion light years total. We only see our 90 billion light year bubble, because everything outside that is moving faster than the speed of light relative to us.
Let's say someone's standing on a planet somewhere in the far off direction (the one where there's 8 times more universe than we can observe). If they're being pushed along by expansion at roughly the same pace as us relative to their surroundings, they should also perceive themselves as being in a bubble of universe that's 90 billion light year across.
Now, who's to say that between what they perceive as the edge and what we perceive as the edge, there's not hundreds of billions of light years of universe that neither of us can see? If our observable edge is one tenth away from the actual edge in one direction and their observable edge is one tenth away from the actual edge in the other direction, then there's 540 billion light years of universe between us that neither of us can see.
The middle that phycisist and cosmologists claim doesn't exist could be in between. We could just be moving away from it so fast that we'll never be able to see it and the true edge of the universe is moving even faster than us, so we'll never be able to see that either.
I don't consider this a closed subject at all.
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Post by c64 on May 22, 2018 19:44:06 GMT
Light can't go backwards unless you break the seed of light barrier. What happens is that the energy of the photons changes due to the Doppler Effect.
The Hubble Telescope uses this to measure the velocity of stars and galaxies. When something is approaching fast, the light spectrum it emits is moved towards (and beyond) blue. If something is moving away, the spectrum moves towards red.
Keep in mind that light is "in the middle" of the electromagnetic spectrum. Radio transmitters would emit visible light when hurled towards the observer fast enough.
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Post by the light works on May 22, 2018 20:34:49 GMT
Light can't go backwards unless you break the seed of light barrier. What happens is that the energy of the photons changes due to the Doppler Effect. The Hubble Telescope uses this to measure the velocity of stars and galaxies. When something is approaching fast, the light spectrum it emits is moved towards (and beyond) blue. If something is moving away, the spectrum moves towards red. Keep in mind that light is "in the middle" of the electromagnetic spectrum. Radio transmitters would emit visible light when hurled towards the observer fast enough. hm. for some reason I had always thought radio was higher frequency than light. maybe I'd never looked at the full EM spectrum broken down. |
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Post by c64 on May 22, 2018 20:47:17 GMT
Light can't go backwards unless you break the seed of light barrier. What happens is that the energy of the photons changes due to the Doppler Effect. The Hubble Telescope uses this to measure the velocity of stars and galaxies. When something is approaching fast, the light spectrum it emits is moved towards (and beyond) blue. If something is moving away, the spectrum moves towards red. Keep in mind that light is "in the middle" of the electromagnetic spectrum. Radio transmitters would emit visible light when hurled towards the observer fast enough. hm. for some reason I had always thought radio was higher frequency than light. maybe I'd never looked at the full EM spectrum broken down. UV light is the border between "non-ionizing" radio waves and "ionizing" radio waves. Radio transmissions are not ionizing, they are harmless. UV light, X-rays, gamma-rays, etc are ionizing. And ionizing DNA-molecules is a real bad thing. Modern microchips use structures way too fine for visible light. While the processor of a C64 was produced using infra-red light, modern processors have to be made using X-rays. Currently "normal" X-rays are also almost to coarse in wavelength, they use special high-energy X-rays and may switch to gamma rays eventually. |
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Post by the light works on May 22, 2018 20:58:38 GMT
hm. for some reason I had always thought radio was higher frequency than light. maybe I'd never looked at the full EM spectrum broken down. UV light is the border between "non-ionizing" radio waves and "ionizing" radio waves. Radio transmissions are not ionizing, they are harmless. UV light, X-rays, gamma-rays, etc are ionizing. And ionizing DNA-molecules is a real bad thing. Modern microchips use structures way too fine for visible light. While the processor of a C64 was produced using infra-red light, modern processors have to be made using X-rays. Currently "normal" X-rays are also almost to coarse in wavelength, they use special high-energy X-rays and may switch to gamma rays eventually. I know radio waves are not ionizing and x rays are - but I had assumed radio waves were between visible light and xrays. - like I said, never really paid close attention to the breakdown of the EM spectrum. |
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Post by GTCGreg on May 23, 2018 1:02:28 GMT
Radio waves are actually the lowest frequencies (longest wavelengths) in the EM spectrum.  |
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Post by the light works on May 23, 2018 1:13:15 GMT
Radio waves are actually the lowest frequencies (longest wavelengths) in the EM spectrum. EMF is a lot lower frequency. |
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Post by GTCGreg on May 23, 2018 3:11:22 GMT
EMF is just a fancy name for voltage and it goes all the way down to DC. (Zero Hz.)
Frequencies in the range of 1mHz to 100Hz are considered ULF(Ultra low frequency). 1mHz is one cycle every 1000 seconds.
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Post by the light works on May 23, 2018 4:00:04 GMT
EMF is just a fancy name for voltage and it goes all the way down to DC. (Zero Hz.) Frequencies in the range of 1mHz to 100Hz are considered ULF(Ultra low frequency). 1mHz is one cycle every 1000 seconds. no, EMF is a magnetic field caused by an alternating current. and yes I have instruments which detect it, and depending on the source, it has a surprisingly large transmission range. |
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Post by GTCGreg on May 23, 2018 4:16:20 GMT
EMF is just a fancy name for voltage and it goes all the way down to DC. (Zero Hz.) Frequencies in the range of 1mHz to 100Hz are considered ULF(Ultra low frequency). 1mHz is one cycle every 1000 seconds. no, EMF is a magnetic field caused by an alternating current. and yes I have instruments which detect it, and depending on the source, it has a surprisingly large transmission range. Actually, we are both right. EMF can stand for Electro Magnetic Field which is, as you state, a megnetic field caused by an electric current flow and it also can stand for Electro Motive Force, which is voltage. en.wikipedia.org/wiki/Electromagnetic_fielden.wikipedia.org/wiki/Electromotive_forceI also have an instrument that can detect it. It's my iPhone. Not only can it detect it. but can plot it in three dimensions. |
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Post by the light works on May 23, 2018 4:24:42 GMT
no, EMF is a magnetic field caused by an alternating current. and yes I have instruments which detect it, and depending on the source, it has a surprisingly large transmission range. Actually, we a both right. EMF can stand for Electro Magnetic Field which is, as you state, a megnetic field caused by an electric current flow and it also can stand for Electro Motive Force, which is voltage. en.wikipedia.org/wiki/Electromagnetic_fielden.wikipedia.org/wiki/Electromotive_forceI also have an instrument that can detect it. It's my iPhone. Not only can it detect it. but can plot it in three dimensions. well, that's an app I don't think google play has. but sure enough. I found an app. we'll see if it works for my needs or is just a gimmick. that way even if I leave my non contact tracers at home, I usually still have my phone with me. |
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Post by the light works on May 23, 2018 4:29:09 GMT
nope, there's a magnetic field sensor, but nothing like my non contact testers or my amplifier probes.
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Post by GTCGreg on May 23, 2018 4:31:49 GMT
well, that's an app I don't think google play has. but sure enough. I found an app. we'll see if it works for my needs or is just a gimmick. that way even if I leave my non contact tracers at home, I usually still have my phone with me. The app on my iPhone detects the magnetic field but not the electrostatic one. Most non-contact voltage detectors sense the electrostatic field. I don't know what the Android phones detect but I suspect it's also the magnetic field. |
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Post by the light works on May 23, 2018 4:33:22 GMT
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Post by the light works on May 23, 2018 4:37:02 GMT
well, that's an app I don't think google play has. but sure enough. I found an app. we'll see if it works for my needs or is just a gimmick. that way even if I leave my non contact tracers at home, I usually still have my phone with me. The app on my iPhone detects the magnetic field but not the electrostatic one. Most non-contact voltage detectors sense the electrostatic field. I don't know what the Android phones detect but I suspect it's also the magnetic field. they use the compass module in the phone. they may be able to tune it to pick up 60hz AC, but apparently they don't have it yet. |
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Post by GTCGreg on May 23, 2018 4:45:51 GMT
Never saw that. Looks like something that would be real handy in your line of work. And $60 isn't bad at all if it works like they claim. Too bad they don't have one for iPhones. FLIR is another smart-phone product that you could probably make use of in both your lines of work. But it's rather on the pricey side. www.flir.com/products/flir-one-pro/ |
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