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PostPosted: Tue Mar 30, 2010 6:52 pm 
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As far as I'm aware time and distance is based on the speed of light, a
universal constant.

Which time would this be? Oh you mean the time we invented based on the Earth rotating in 24 hours. I see. Where and when can we apply this kind of time in the rest of the Universe?


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PostPosted: Tue Mar 30, 2010 7:03 pm 
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Quasar wrote:
Which time would this be? Oh you mean the time we invented based on the Earth rotating in 24 hours. I see. Where and when can we apply this kind of time in the rest of the Universe?

Anywhere you like. The units of measurement are arbitrary. You simply have to make allowances such as those that we already make, even within the confines of the Earth's atmosphere - think GPS, Relativity and so on. Time and space are not fixed, as you know. We are aware of this and make allowances when and where necessary.

I really don't get your point, Quasar.

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PostPosted: Tue Mar 30, 2010 7:20 pm 
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joe wrote:
Quasar wrote:
Which time would this be? Oh you mean the time we invented based on the Earth rotating in 24 hours. I see. Where and when can we apply this kind of time in the rest of the Universe?

Anywhere you like. The units of measurement are arbitrary. You simply have to make allowances such as those that we already make, even within the confines of the Earth's atmosphere - think GPS, Relativity and so on. Time and space are not fixed, as you know. We are aware of this and make allowances when and where necessary.

I really don't get your point, Quasar.

Ok you make the assumption that 'your time' is correct and can be used to measure how old the Universe is. Here's an hypothetical:- You are in a distant part of the Universe looking back at Earth with a superb telescope, you notice that when on Earth you measured that it took exactly 24 hours to rotate but when you look through the telescope you notice that from where you are in the Universe it is only taking the Earth 18 hours to rotate. What would you conclude from this? Quite simple, the gravity field you are in has a completely different prospective of time.
But then a problem arises, when i was on Earth I used the 24 hours split into hours and then seconds to gauge the speed of light. Example 300,000KM per Earth second. Now we have a problem, an Earth second has changed, the speed of light is still the same and always will be but our relative viewpoint of what a 'second' means has. So which second is correct? The second while you were on Earth or the new second I just measured? The speed of light always remains the same, our prospective of what a second means can change depending on where you are in the Universe. Your clock is about as much use as a chocolate fireguard my friend. :lol:


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PostPosted: Tue Mar 30, 2010 8:55 pm 
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On my part of the Earth, it takes 23 hours, 56 minutes and 4+ seconds
to rotate.


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PostPosted: Tue Mar 30, 2010 8:59 pm 
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But all of your objections are covered by Einstein's relativity theories. It's not something of which we are unaware. If you are travelling at near light speed then the diameter of the visible universe will appear smaller and it will take less time to travel from end to end. Similarly, if you are in the presence of a very strong gravitational field, near a black hole for example, time and space will again be effected. My clock is not as useless as a chocolate fireguard because I can calculate the differences using my clock as a reference.

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PostPosted: Tue Mar 30, 2010 10:42 pm 
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I was hoping you’d say that and I have a reply to it. Lets take this scenario a little further. Ok Joe we have two perspective’s of time, neither perspective is interchangeable with the other because of the effect of the gravity field and is only relative to each respective party. The speed of light remains the same to both parties.
Hypothetical number 2:-
Glad you mentioned black holes because I’m going to use it as an example. OK, You and Fred are on a spaceship and you both calibrate your clocks exactly the same. Fred goes off in his probe and sits very near a black hole and Fred’s Biological clock and atomic clock slow down according to us but he observes things as normal and his clock seems to be ticking as normal from his viewpoint.
You are in a position away from the effects of the black hole and everything seems fine to you.
I’m in a spaceship an equal distance from the pair of you and I have a telescope aimed at the pair of you watching your atomic clocks. I fire a beam of light energy at you Joe and watched your atomic clock to see how long it takes to hit you according to your clock. It takes one second. I fire the beam and watch Fred’s clock, according to his clock it took a millionth of a second. The black hole slowed Fred’s clock down from our prospective but from his prospective all seems well. From Fred’s point of view the light beam hit his clock at one second the same as yours Joe. When we look at Fred we observe that he is moving in mega slow motion and his clock only ticks once every few hours, we observed the light hitting his clock in a millionth of a second, he observed it hitting his clock in one second. If Fred observes the light hitting his clock in one millionth of a second then from his point of view light speed has increased by a huge margin. The light hit the clock but there are two possibilities of when it struck. One from each respective party. Who is right and who is wrong?
Remember the double slit experiment? There are two possibilties that can take place and the light can be in two places at once. But this time instead of being in two places on the rear screen as in the double slit experiment they are at two places in time. Emmmmm Things are very different from what we might think they are.


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PostPosted: Tue Mar 30, 2010 11:13 pm 
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Quasar wrote:
I fire the beam and watch Fred’s clock, according it his clock it took a millionth of a second.
Quasar wrote:
he observed it hitting his clock in one second.
Quasar wrote:
If Fred observes the light hitting his clock in one millionth of a second

You've got me confused now. :D

I'm no expert but I don't think you have described the realistic behavior of the light beams and clocks. First of all the light beam hitting Fred has to return to you before you can see when it hit the clock. It will be effected by the black hole's gravity too. I also don't think he will see the light beam hit Joe at the same time as you do therefore I don't think it's as simple as you say. But the point is that no one is right or wrong. However we can calculate what is happening at all times and places.

Given that the vast majority of the visual universe is inter-stellar/galactic vacuum, we have to make the assumption that gravity is the same throughout. It may not be but we would need some evidence of that.

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PostPosted: Thu Apr 01, 2010 4:55 pm 
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I took it for granted that you would have already taken into consideration the calculations needed because I have to observe both clocks but never mind. Forget the effect of the black hole on light, it is not important, it was an hypotheticol and the idea was to just give a general scenario of effect.
How can you possibly assume that gravity will be the same in our galaxy in comparison to a galaxy of perhaps 10 times the mass of ours? How can you assume the centrifugal effect of one spinning spiral galaxy will be the same as another spinning 10 times faster with a greater mass?
Like I said before Joe, you will never be able to get out of you're bucket.


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PostPosted: Thu Apr 01, 2010 5:23 pm 
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Quasar wrote:
How can you possibly assume that gravity will be the same in our galaxy in comparison to a galaxy of perhaps 10 times the mass of ours?

When I say that gravity is the same throughout the universe I mean that Newton's/Einstein's equations will describe gravity in the same way as it does here. The amount of mass producing a gravitaional force is irrelevant, the equations still work, therefore, a larger galaxy produces a stronger gravitational field, but it's still the "same" gravity. There is, as far as we know, no other kind of gravity that can't be described by Newton's/Einstein's equations.

This is not, as you say, a biased perspective. We expect gravity to be weaker on the Moon and stronger close to a black hole. I don't see why we can't assume that elsewhere in the universe the same assumptions can be made.

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PostPosted: Sun Apr 04, 2010 7:59 pm 
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joe wrote:
Quasar wrote:
How can you possibly assume that gravity will be the same in our galaxy in comparison to a galaxy of perhaps 10 times the mass of ours?

When I say that gravity is the same throughout the universe I mean that Newton's/Einstein's equations will describe gravity in the same way as it does here. The amount of mass producing a gravitaional force is irrelevant, the equations still work, therefore, a larger galaxy produces a stronger gravitational field, but it's still the "same" gravity. There is, as far as we know, no other kind of gravity that can't be described by Newton's/Einstein's equations.

This is not, as you say, a biased perspective. We expect gravity to be weaker on the Moon and stronger close to a black hole. I don't see why we can't assume that elsewhere in the universe the same assumptions can be made.

Makes no odds, you are arguing against the fact that all things are relative. You're own particular prospective of what time means is not applicable to the rest of the Universe as such. You are arguing that you're own idea of what a year means is applicable across many different gravitational fields and across vast voids of space. All the calculations made within one relativalistic viewpoint although they are relevant to you and can explain things to you personally cannot be possibly passed outside that viewpoint. It would be the same as calculating the age of another Universe you cannot see based on calculations of a Universe you can see. The bucket i keep refering to is the same effect. The only possible way to make any calculation would have to be based on a none relative viewpoint, based on the idea that you have no idea what time means outside your own clock.


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PostPosted: Sun Apr 04, 2010 11:31 pm 
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Quasar wrote:
Makes no odds, you are arguing against the fact that all things are relative.

I don't think I am. You could try again to explain why as I seem to be missing something, obviously.

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PostPosted: Mon Apr 12, 2010 9:16 am 
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joe wrote:
Quasar wrote:
Makes no odds, you are arguing against the fact that all things are relative.

I don't think I am. You could try again to explain why as I seem to be missing something, obviously.

It is quite simple Joe, Einstein points out that all things are relative, that means our prospective of what time means is only, and can only ever be relative to us and our environment in which we perceive it. As you know we live in a vast Universe in which we are a drop in a billion ocean's of dimension, time and space. We do not have the keys as yet to be able be onlookers and we can only assume that we think we are correct in our calculations of what it all means. Seems strange to me that a civilization like ours doesn't have the first clue about how the Quantum field really works, doesn't even know what gravity really is, struggles to understand the full workings of the Electromagnetic spectrum but claims to know how old the Universe is? I'd say we need to understand things closer to home before we start making predictions on that scale. Afterall, the whole Universe is made up of Quantum and gravitational fields, which like I have said, we don't really know much about at all.


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PostPosted: Mon Apr 12, 2010 9:39 am 
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Yes, Quasar, I see and understand that but relativity is used to make calculations FROM other perspectives. It is the reason it works. I don't know what you mean by "a billion oceans of dimension, time and space". Working with three spacial and one temporal dimension scientists calculate the size and age of the universe according to our best theory of how the universe evolved. Can you tell me what other perspective they have failed to take into consideration, or indeed, could take into consideration?

Quote:
Seems strange to me that a civilization like ours doesn't have the first clue about how the Quantum field really works, doesn't even know what gravity really is, struggles to understand the full workings of the Electromagnetic spectrum but claims to know how old the Universe is

It's clear that scientists can only hypothesise armed with current knowledge. Is there any point in saying that as we don't yet know everything, we can't construct a theory?

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PostPosted: Mon Apr 12, 2010 10:11 am 
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joe wrote:
Yes, Quasar, I see and understand that but relativity is used to make calculations FROM other perspectives. It is the reason it works. I don't know what you mean by "a billion oceans of dimension, time and space". Working with three spacial and one temporal dimension scientists calculate the size and age of the universe according to our best theory of how the universe evolved. Can you tell me what other perspective they have failed to take into consideration, or indeed, could take into consideration?

Quote:
Seems strange to me that a civilization like ours doesn't have the first clue about how the Quantum field really works, doesn't even know what gravity really is, struggles to understand the full workings of the Electromagnetic spectrum but claims to know how old the Universe is

It's clear that scientists can only hypothesise armed with current knowledge. Is there any point in saying that as we don't yet know everything, we can't construct a theory?


Because we know very little about how it all began, we cannot be sure how things have evolved. We do not know if time evolved into what we see today or if it was just a constant from the beginning, we do not know if gravity evolved or indeed how the Quantum field evolved. In essence we are trying to fathem the workings of a clock when we don't know for sure that the clock was working in the way we assume it was.
That is the problem we all face Joe, the word 'assume'. We all assume things when we don't know what really happened at all. When we make a calculation on Earth for anything, there are fields which are always filled in. For example if we work out the Kinetic energy of a car moving down a road, we know all the data that is required such as mass, velocity, time and the gravity of the Earth repelling it. That gives us just about all we need. When we make calculations for the age of the Universe, a lot of those fields are missing and replaced by assumptions. A calculation based on an assumption made by someone in the process is just about as flawed as you could possibly be.


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PostPosted: Mon Apr 12, 2010 10:55 am 
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I'll give you an example of 'assuming' which take place. The observable Universe for one: we observe the Universe and watch it's behaviour very closely. We have deduced from it's behaviour that it has an overall mass. The mass is linked to how old the observable Universe is. But there is a catch, there isn't enough observable mass to reflect it's behaviour so in order for this madness to carry on, we invent some - dark matter. So now for the age of the Universe to be X number of years old, we base it on a calculation that 'assumes' dark matter exists even though we never saw any of it, or saw any causal behaviour related to it. Magic!!!!


Last edited by Quasar on Mon Apr 12, 2010 5:06 pm, edited 1 time in total.

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