Are we alone in the universe?

[Splog]

The ageing process only slows down for someone outside your frame of reference...You will still age 'normally'. Those same people will appear to age quickly from your frame of reference. Its the Twins Paradox. However this also appears to question on who is actually moving at the speed of light, would it be you or them - as you are both moving away from each other at the same speed.

EDIT: just to qualify the above...I stopped Physics at 16 so don't take that as fact haha

Not true. If you flew away into outer space at a speed very close to the SOL (speed of light) for a year or so and then returned to Earth, you would have aged only one or two years or so, which would be normal as that is the time you have travelled, however that time would be very much slower than for those on Earth...... You would have travelled forward in time... Those who you left behind would have died many, many years ago and probably turned to dust.

Yes you are moving away from each other in one sense i.e. relative to each other, but you would both be encompassed in your own time frame......

 

[Splog]

Ah you posted as I was typing and this is what I was trying to say! lol

The last part is too much for me lol I understand what you mean and the concept, I was even thinking that maybe acceleration is key but then they are both accelerating. I guess that's the odd thing about light! lol

Yup! ... The speed of light is pretty much a constant

PS: Sorry for posting so much in this thread .... I just love the subject

 

[custodian]

Of course you will also put on weight at an amazing rate. One of the standard relativuty equations is:

m=m0 divided by the square root of (1 - v2/c2)

where m is your mass at a given velocity and m0 is your mass at rest; v is your velocity and c is the speed of light. As v2/c2 approaches 1, then you will see that your mass becomes infinite.

Pick the bones out of that.

 

[Rolyratman]

Of course you will also put on weight at an amazing rate. One of the standard relativuty equations is:

m=m0 divided by the square root of (1 - v2/c2)

where m is your mass at a given velocity and m0 is your mass at rest; v is your velocity and c is the speed of light. As v2/c2 approaches 1, then you will see that your mass becomes infinite.

Pick the bones out of that.

I don't need any help there, Coca Cola has the weight gain covered...

If we did ever somehow make a craft capable of SOL flight I wonder how long an emergency stop would take...:bonk:

 

[AndyB1976]

Not true. If you flew away into outer space at a speed very close to the SOL (speed of light) for a year or so and then returned to Earth, you would have aged only one or two years or so, which would be normal as that is the time you have travelled, however that time would be very much slower than for those on Earth...... You would have travelled forward in time... Those who you left behind would have died many, many years ago and probably turned to dust.

Yes you are moving away from each other in one sense i.e. relative to each other, but you would both be encompassed in your own time frame......

I didnt word that very well..The ageing process only slows down for someone outside your frame of reference

I meant that the ageing process only slows down for you - the person moving, outside their - (the observers) frame of reference. For you..you still age in earth years so to speak. You can see we agree with the remainder

 

[dinners]

Cheers Phil I'll certainly watch that

Let me know what you think

 

[AndyB1976]

Not true. If you flew away into outer space at a speed very close to the SOL (speed of light) for a year or so and then returned to Earth, you would have aged only one or two years or so, which would be normal as that is the time you have travelled, however that time would be very much slower than for those on Earth...... You would have travelled forward in time... Those who you left behind would have died many, many years ago and probably turned to dust.

Yes you are moving away from each other in one sense i.e. relative to each other, but you would both be encompassed in your own time frame......

Yeah...but who would age? it would be dependant on the frame of reference of the obeserver

 

[Splog]

I didnt word that very well..The ageing process only slows down for someone outside your frame of reference

I meant that the ageing process only slows down for you - the person moving, outside their - (the observers) frame of reference. For you..you still age in earth years so to speak. You can see we agree with the remainder

Not sure I follow that Time is fluid and flows at different speeds depending on many things! ... For example mass will also slow down time. If you were walking on a planet 1000 times the size of the Earth you would experience time running slower although not by much. If you were travelling super fast then time would slow down! but for you time would still feel the same, it's just that for those left on Earth time would be passing quicker but wouldn't feel any different to them! .... Think of it as travelling forward into the future .... i.e. time travel.

 

[Splog]

Yeah...but who would age? it would be dependant on the frame of reference of the obeserver

If it were possible for an observer to witness? .... then yes they would see time pass more slowly on Earth..... but that would be relative to the observers frame of reference as you say.

 

[gman]

Great if we can suddenly create a space craft that can achieve those speeds but based on the fastest we have managed so far it would take 4,500 years!!

I reckon it would be more likely that we'd develop something like the theory in that film Event Horizon, so rather than looking at how to go faster we simply (aye, pure dead simple) fold space instead in order to arrive at a point almost immediately!

I guess this is more along the lines of teleporting which I believe we can already do - well for basic matter or something. Can't quite remember.

 

[trencheel303]

The 8 minutes is relative to us not to the light from the sun... time doesn't exist for light.... As an object approaches the speed of light, time will slow down more and more to the point where time would stop if you actually achieved the 186,000 miles a second .... Time simply gets slower the faster you go. If your journey really involved instantly being able to travel at the speed of light then time would stop for you also .... therefore you would arrive instantly as no time will have passed.

As an aside the way I think of light speed is: imagine being able to fly around the Earth approximately 7 times every second .....

I don't understand... if time doesn't exist for light then how come it takes time to get somewhere. Like sunlight taking around 8 minutes to hit the earth, etc.

I've never understood the notion that the faster you go the slower time goes...

 

[Big Andy]

I read this thread last night and it made my head spin, I thought a fresh look in day light might help. :bonk: Wrong. But at least I've worked out the reason for my excess weight, it's because I move to fast Err, I think.

Keep it coming, even though I have trouble getting my head around this I still find it fascinating.

 

[arclight]

I don't understand... if time doesn't exist for light then how come it takes time to get somewhere. Like sunlight taking around 8 minutes to hit the earth, etc.

I've never understood the notion that the faster you go the slower time goes...

You and millions of others - me included.

 

[MartynK]

I haven't a clue if there is "intelligent" life anywhere else, but I find it quite a reasonable supposition. Whether we would be able to recognise it, or communicate with it, is another matter because we're constrained by our own knowledge and understanding.

I'm more interested in what is happening here. AFAIK, most palaeoanthropologists agree that we haven't descended from apes. We have a common ancestor, but the line split several million years ago. Why, what caused this, was it a chance event? We haven't been around for very long at all, and evolution is still continuing, so what is going to happen over the next 2 - 3 million years?

 

[simonw]

Almost certainly there is life out there.

However we better hope it never makes contact with us if the history of humans is anything to go by. When one "more advanced" part of the human race has met a "less advanced" part the result has normally been devastation for the advanced part (North American Indians, Australian Aboriginals, etc etc)

Any life form that is capable of reaching earth is going to be far more advanced than we are and we are unlikey to benefit from contact.

 

[AndyB1976]

Of course you will also put on weight at an amazing rate. One of the standard relativuty equations is:

m=m0 divided by the square root of (1 - v2/c2)

where m is your mass at a given velocity and m0 is your mass at rest; v is your velocity and c is the speed of light. As v2/c2 approaches 1, then you will see that your mass becomes infinite.

Pick the bones out of that.

Not sure I follow that Time is fluid and flows at different speeds depending on many things! ... For example mass will also slow down time. If you were walking on a planet 1000 times the size of the Earth you would experience time running slower although not by much. If you were travelling super fast then time would slow down! but for you time would still feel the same, it's just that for those left on Earth time would be passing quicker but wouldn't feel any different to them! .... Think of it as travelling forward into the future .... i.e. time travel.

So larger mass slows you down, and more energy slows you down. The Mass Energy Equivalence (E=M), infinite energy = infinite mass.

This can only occur outside our known laws of physics, so this might be the cause of a black hole?

 

[CT]

Too much for me I just don't get it! On the one hand they say the universe is infinite (I can't comprehend infinity anyway and is it even possible?) then the video claims the universe to be 78 billion miles across, so what's beyond that then? The whole thing could be in a jar on someone's mantlepiece! :shrug:

As for other life out there somewhere, I'd say it has to be a racing certainty, but quite why we should expect them to be friendly I don't know - we can't get on with each other down here! We can't tavel fast enough and we don't live long enough to reach even the closest star to us and we possibly never will.

 

[Splog]

Too much for me I just don't get it! On the one hand they say the universe is infinite (I can't comprehend infinity anyway and is it even possible?) then the video claims the universe to be 78 billion miles across, so what's beyond that then? The whole thing could be in a jar on someone's mantlepiece! :shrug:

As for other life out there somewhere, I'd say it has to be a racing certainty, but quite why we should expect them to be friendly I don't know - we can't get on with each other down here! We can't tavel fast enough and we don't live long enough to reach even the closest star to us and we possibly never will.

But maybe ET can live long enough and travel fast enough to reach us.

 

[gman]

The whole thing could be in a jar on someone's mantlepiece! :shrug:

Bit like the "Men in Black" theory! lol

 

[gman]

On the one hand they say the universe is infinite (I can't comprehend infinity anyway and is it even possible?) then the video claims the universe to be 78 billion miles across, so what's beyond that then?

You would think us humans would learn from past experience, it wasn't all that long ago that we thought the earth was flat. Why do we think the same of the universe? It could be round but then there must be boundaries somewhere? Does it just fold on itself?

It's kind of strange how we can't comprehend infinity. We understand what it is but when it comes to the universe's dimensions it's a whole different ball game! lol

 

[Doog]

We (humans) can see further and further into this universe, making it larger and larger in our mind. We, though, seem to be stuck in finding things smaller than atoms or sub atomic particles. So....:shrug: are we to understand that we are closer to the smallest things in the universe than the largest. Or... is it possible that our senses are only capable of seeing what we see, and in fact there is more surrounding our bodies than meets the eye. Could it be this parallel universe of which we speak? And if it is, could it be that those things which we are finding so many billion light years away from us are actually things which are just at the edge of our five sense capability but are actually closer to us than what we think they are. It's a paradox for sure.

 

[Lynton]

Not true. If you flew away into outer space at a speed very close to the SOL (speed of light) for a year or so and then returned to Earth, you would have aged only one or two years or so, which would be normal as that is the time you have travelled, however that time would be very much slower than for those on Earth...... You would have travelled forward in time... Those who you left behind would have died many, many years ago and probably turned to dust.

Yes you are moving away from each other in one sense i.e. relative to each other, but you would both be encompassed in your own time frame......

Either I am being a thicket or I genuinely don't get it..........

If I were to hop into my super duper spacecraft that can travel at the speed of light and head off in a straight line for a year, turn around and come back taking another year, then surely the time I have been away is 2 years, and I'll be sat here on 21/1/2013?

How can it be anything else?

 

[gman]

Either I am being a thicket or I genuinely don't get it..........

lol I'm right there with you! I understand how time is relative to a frame of reference etc but it's still a mind screw.

Was having a wee browse online and the words quantum electrodynamics and quantum field theory are coming up. As soon as I see the word "quantum" being used I know it's time to stop looking!

Apparently "About Time" by Paul Davies is supposed to be good at explaining it in more understandable terms - but for me this is one of those topics you could spend a lot of time on and still end up without a definitive answer!

The one thing I know for sure about "time" is that it's too damn important to waste!

 

[AndyB1976]

I read some other info relating to the fact mentioned earlier, that infinite energy is required to travel at the speed of light therefore would require infinite mass. So you would need to consume all the mass in the universe to have the energy required.

All that energy..then nowhere to go

 

[gman]

I read some other info relating to the fact mentioned earlier, that infinite energy is required to travel at the speed of light therefore would require infinite mass. So you would need to consume all the mass in the universe to have the energy required.

All that energy..then nowhere to go

But light travels at the speed of light? But then what exactly is light and does it really travel?

Take electricity, it's most commonly thought to travel at the speed of light but in fact it actually travels really slowly. It just seems like it because the electrons are already there and are simply being moved!

Bring on the

 

[AndyB1976]

Does anyone else on this thread feel like they've been 'outted' from the geek clauset

 

[andy_fozzy]

I do apologise for my lack of input into this thread.
I've just had a catch up, and it's such an interesting topic.

Cheers for all your input.

Keep it going!

 

[Splog]

I do apologise for my lack of input into this thread.
I've just had a catch up, and it's such an interesting topic.

Cheers for all your input.

Keep it going!

Okay, how about more time travel ....


The usual example is ...... Imagine flying away on a space ship to Alpha Centauri (4.2 light years away)

Travelling at:
10% Speed of Light then Earth time would be 42 years, Space ship clock 41.8 years
25% Speed of Light then Earth time would be 16.8 years, Space ship clock 16.3 years
50% Speed of Light then Earth time would be 8.4 years, Space ship clock 7.3 years
75% Speed of Light then Earth time would be 5.6 years, Space ship clock 3.7 years
90% Speed of Light then Earth time would be 4.7 years, Space ship clock 2.0 years
95% Speed of Light then Earth time would be 4.4 years, Space ship clock 1.4 years
99% Speed of Light then Earth time would be 4.2 years, Space ship clock 218 days
99.9% Speed of Light then Earth time would be 4.2 years, Space ship clock 69 days
99.99% Speed of Light then Earth time would be 4.2 years, Space ship clock 22 days
99.999% Speed of Light then Earth time would be 4.2 years, Space ship clock 6.9 days
99.9999% Speed of Light then Earth time would be 4.2 years, Space ship clock 52 hours.

At 99.9999% the SOL You would be able to travel to the centre of our Galaxy in about 40 years or so! .... For a Brownie point work out how much time would have passed on Earth for your 40 years of space travel

 

[u8myufo]

Okay, how about more time travel ....


The usual example is ...... Imagine flying away on a space ship to Alpha Centauri (4.2 light years away)

Travelling at:
10% Speed of Light then Earth time would be 42 years, Space ship clock 41.8 years
25% Speed of Light then Earth time would be 16.8 years, Space ship clock 16.3 years
50% Speed of Light then Earth time would be 8.4 years, Space ship clock 7.3 years
75% Speed of Light then Earth time would be 5.6 years, Space ship clock 3.7 years
90% Speed of Light then Earth time would be 4.7 years, Space ship clock 2.0 years
95% Speed of Light then Earth time would be 4.4 years, Space ship clock 1.4 years
99% Speed of Light then Earth time would be 4.2 years, Space ship clock 218 days
99.9% Speed of Light then Earth time would be 4.2 years, Space ship clock 69 days
99.99% Speed of Light then Earth time would be 4.2 years, Space ship clock 22 days
99.999% Speed of Light then Earth time would be 4.2 years, Space ship clock 6.9 days
99.9999% Speed of Light then Earth time would be 4.2 years, Space ship clock 52 hours.

At 99.9999% the SOL You would be able to travel to the centre of our Galaxy in about 40 years or so! .... For a Brownie point work out how much time would have passed on Earth for your 40 years of space travel

Give me a break will you :shake: I have only just got around to understanding the shutter speed of my camera

 

[dinners]

All this talk of time - I might have re-watch 2001 A Sapce Odysey now.

 

[Splog]

Give me a break will you :shake: I have only just got around to understanding the shutter speed of my camera

Why? ...... it never changes, it's always the same