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I've been thinking, and I have a question for you all. Is there any possible way that you could look in a mirror and see nothing, even if you look in all wavelengths? If you answer this then I'll ask the next question.

[Guille]

Maybe, maybe there....

It woul dbe a har djob, but nto impossible:

Basically it's a very simple thing to do:

Go to transilvania, let mr. Dracula bight you in your neck, and then you wait until the next whole moon, from then on, you won't be reflected on any mirror.

But I can tell you by experience that it's not easy to find count Dracula.

[dleviwing]

Sub;
If your vision was only of those wavelengths that are not reflected by the mirror (IR/UV) then it is possible that you would not see your reflection. Mirror are designed to reflect visible light, not all EM radiation.

[subversion]

boy I'm really excited about this thread! Good answers, good answers, however, let's assume, as it was said to be difficult, that we can't find count Dracula, and let's also assume that we have a perfect mirror which can reflect all wavelengths. Given these assumptions, is there any possible way you can think of that you would look in the mirror and see nothing. Because if not...

[Guille]

Still, perfect mirrors don't exist, not only because perfection doesn't exist, but because the streight line doesn't exist.

[subversion]

whether perfection exists does not bear on the fact that we strive for nothing less. In this light I want to tell you that streight is spelled straight if it is to be spelled perfectly. But then again what do they know right? Notwithstanding any of these facts, let us touch on the matter at hand, which is not whether or not we can build a perfect mirror. I'm convinced we CAN build a perfect mirror, but what do I know?

We are discussing theoretically whether a perfect mirror could ever be "blank" (i.e. show nothing) if you were to look at it's reflective surface. The reason this is important is because if we decide that a mirror should never be "blank" then I have discovered one of two important things. Either a.) mirrors CAN be blank and I've realized how or b.) the truth is something too crazy for me to say right now until we decide whether mirrors can or can't be blank. Obviously if we decide then I can use that evidence to say that b.) is true and then tell you.

[subversion]

I think I'll continue on with describing my time reflection device. As far as we've ascertained there's no reason that you should look in a mirror and see nothing.

I'm not sure if this device would really work or not, but I thought of it one day, when I was thinking about how if you look in the mirror, you're really seeing yourself in the past, since it takes the light a certain amount of time to get to you. I was thinking, wouldn't it be cool it there was a giant mirror about 32 million light years away from us in outer-space. Then if we looked at it with a really powerful telescope we could see the earth as it was during the age of the dinosaurs, approx. 65 mya or twice the distance to the mirror in light years.

I thought this was pretty cool but then I started thinking, in order for there to be a delay between what the mirror shows and what is actually happening, then time inside the mirror has to appear to slow down as the mirror is moving or drifting away from you. This is just due to the fact that light travels with finite speed.

So if you launched a giant mirror into outerspace in the year 2005, and it was travelling at half the speed of light, then when the mirror was a certain distance away you'd still always see an image of 2005, because the light has to travel twice as far as the distance to the mirror. Since the distance the light must travel is increasing at twice the speed that the mirror is moving, the distance the light must travel to reach your eye is increasing at the speed of light. So it seems like time would be paused in a mirror traveling at one half C, and if the mirror went faster than 1/2 C, time would flow in reverse in the mirror. This doesn't make sense because it suggest you could see events in the past from when before the mirror was ever built. In fact, it suggests you could see any event in the past, but it would be optically and mechanically very difficult unless you used a lot of mirrors such that you reduce the speed you have to move them. If you have four mirrors, time in the last one would stop if they were all moving directly away from one another at 1/3 C. Somehow it must be impossible to look back in time indefinitely, but I can't figure out why. help would be appreciated

[subversion]

see post above

[Graybeard]

ooops ... should have read all the posts first





Well .... the silver back on the mirror would reflect 100% of the visible electro-magnetic waves .. there maybe frequencies that can pass thru ... i am not sure of all frequencies.

Are you referring to 'mirror symmetry' (parity violation) ??

[Graybeard]

I was thinking, wouldn't it be cool it there was a giant mirror about 32 million light years away from us in outer-space. Then if we looked at it with a really powerful telescope we could see the earth as it was during the age of the dinosaurs, approx. 65 mya or twice the distance to the mirror in light years.

I think i see whats wrong .... But first i need a few answers

The Sunlight that warmed the Dinosaurs and reflected off their hides left the Earth 65mya ..... it is already 65 million light years away

1.. Are we assuming that the mirror is already there .. 65 million light years from earth ??

2.. If 1 is true ... then i think you can see a Tyranosauraus Rex in another 65 million years

3.. Was the mirror placed 32.5 light years from earth 32.5 million years ago ??

4.. If 3 is true ... Then if you look quickly you will see a Tyranosauraus Rex Now !!

5.. All this is assuming that we are ignoring earths spin, rotation, orbital path etc ... in fact is this a mind exercise on special relativity only .. ?? otherwise with gravity it is too complicated for an exercise

if we agree on the above then i think i can see a flaw in the rest of your hypothesis... but i need time to work it out exactly ... but you might like to think about these points and you will probably arrive at the solution before me

a.. possible flaw = the combined speed of any objects motion thru space and its motion thru time is always precisely equal to the speed of light

b.. possible flaw = the light that 'is' the reflection of the earth in 2005 is leaving at light speed ... to freeze it you must travel at light speed ... otherwise the 'image' will leave you behind

c.. possible flaw = If one 'event' is the 'cause' of another, ALL observers agree regardless of their motion, that the 'cause' happened before the 'effect'.

i'm still thinking ..... Greg