Scale of the universe - how to understand?
12-17-2012
, 02:22 AM
Quote:
Quote:
But recently White calculated what would happen if the shape of the ring encircling the spacecraft was adjusted into more of a rounded donut, as opposed to a flat ring. He found in that case, the warp drive could be powered by a mass about the size of a spacecraft like the Voyager 1 probe NASA launched in 1977.
Furthermore, if the intensity of the space warps can be oscillated over time, the energy required is reduced even more, White found.
Furthermore, if the intensity of the space warps can be oscillated over time, the energy required is reduced even more, White found.
Quote:
Also, you are kind of on the right track to understand scale. The 10x repeated is fairly understandable. Of course, you end up at the same understanding that everyone else gets, which is "it is really freaking huge. Way bigger than an elephant."
12-17-2012
, 04:31 AM
12-19-2012
, 03:43 AM
Quote:
12-19-2012
, 04:17 AM
http://www.youtube.com/watch?v=_IVqMXPFYwI
might help too.
For a human with average (western) knowledge, it is difficult to realise about what proportions we are talking here.
Additional issues:
We are talking about the OBSERVABLE universe. Current models estimate that the actual universe is bigger. One might ask: How is that possible, since light is the fastest thing that exists and even if the farthest points are travelling with light, how can be there something "behind"?
First: Nothing with a mass can travel as fast as light. The only reason why light, photons, are doing that is because they have no mass at v (velocitiy) = 0.
Now: How can be there something so far away that light didnt reached us yet? Current models say that has something to do with the expansion of the universe. The expansion does not happen by objects "moving" with their own propulsated speed. Instead: The SPACE itself is expanding. What people are used is: You and I move away, so we have a speed v1 (you) and v2 (me) and these are subject to the usual laws that we know.
Now imagine you and I are standing still, but something inflates the room, the very fabric of space, between us, creating new space, pushing us apart. We still have our speeds, but we may now our speed is not limited to restrictions.
Problem with speed: If i want to accelerate an object, i need energy to do so. The more I want to accelerate it, the more energy i need to do so. Einsteins equation (which are proved and also seen in full effect in suppercollidiers) show that the more i approach the speed of light, the more energy I need - exponentially more energy. Since E=Mc*c, the faster that object becomes, the bigger its mass (this is not a problem with low velocities, like a 10Km/sec, but becomes a critical factor when i approach c (c stands for speed of light)). When i get closer and closer to the speed of light, the objects becomes massiver and massiver, i need more and more energy and it becomes so much that i will never reach the speed of light. Not to mention a tad of really bothering relativistic effects. More to that later.
So: We have a problem. The distances we are talking of are SO huge, that even the best propulsion system, including those who are just tested and somehow in the near future ready for use, are in no way efficient enough. Moon? Sure. But the moon is reaaaaally close. Distance: 1 lightsecond (the distance a lightbeam, photon, would travel during a second).
And thats just the moon. In no way sufficient. In around a billion years, life becomes a problem on earth, so our destiny is, long term, to colonise not just other planets in our solar system, but inevitably other solar systems. These are a tiny little bit further away. The next solar system (and we dont even know what is there) is a bit less than 5 lightyears away. If we have already not so few trouble getting to the moon and back without a monster of ressources we need....can you imagine what such a travel would mean as effort? Even if you would put that amount of ressources in (i guess the whole world would have to work together for free for a couple of decades), it would still be a real undertaking and, with current means, such a travel would take hundreds of years. One way.
Next problem: Relativity. "simultaneous" does not exist. But can be close. Every event is spread from the source with the speed of light. Example: Our sun would from one second to another become dark. the sun is around 8 lightminutes away. So if it happens now, right now there, the event would be by us realised 8 minutes later. It is not easy to syncronise therefore events apart.
Our current level of technology is very crude. Despite we invented computers and lasers, ion propulsion and tons of other stuff, our current knowledge about the nature of the things and (which is THE most important thing) our ability to manipulate our surroundings is very very limited, despite all progress we have done. There is still much much to learn about that. We call it science.
Edit:
There are more problems to us than just that. In our current economic system, we dont do research "by fun", we do it to expect a profit. Note that i didnt said "beneficial effect". We do it for profit. There are exceptions to it (base research), these are done by gov financed universities. The fast majority of current research is done by companies though, and there, only profit counts.
Which means, that our level of science research to the relevant parts to undertake such projects are neglected. We do a lot of research for example into "male performance enhancement", yet, compared to it, very little for improvement on propulsion systems. Stupid example, maybe, but you get the idea. Science is connected to each other, so we need also a better understanding to a load of other fields, for example materials. Alloys. Composites. Energy production (actual: Conversion. You cannot produce energy, only convert one energy form to another).
And much much more to say on all this...
might help too.
For a human with average (western) knowledge, it is difficult to realise about what proportions we are talking here.
Additional issues:
We are talking about the OBSERVABLE universe. Current models estimate that the actual universe is bigger. One might ask: How is that possible, since light is the fastest thing that exists and even if the farthest points are travelling with light, how can be there something "behind"?
First: Nothing with a mass can travel as fast as light. The only reason why light, photons, are doing that is because they have no mass at v (velocitiy) = 0.
Now: How can be there something so far away that light didnt reached us yet? Current models say that has something to do with the expansion of the universe. The expansion does not happen by objects "moving" with their own propulsated speed. Instead: The SPACE itself is expanding. What people are used is: You and I move away, so we have a speed v1 (you) and v2 (me) and these are subject to the usual laws that we know.
Now imagine you and I are standing still, but something inflates the room, the very fabric of space, between us, creating new space, pushing us apart. We still have our speeds, but we may now our speed is not limited to restrictions.
Problem with speed: If i want to accelerate an object, i need energy to do so. The more I want to accelerate it, the more energy i need to do so. Einsteins equation (which are proved and also seen in full effect in suppercollidiers) show that the more i approach the speed of light, the more energy I need - exponentially more energy. Since E=Mc*c, the faster that object becomes, the bigger its mass (this is not a problem with low velocities, like a 10Km/sec, but becomes a critical factor when i approach c (c stands for speed of light)). When i get closer and closer to the speed of light, the objects becomes massiver and massiver, i need more and more energy and it becomes so much that i will never reach the speed of light. Not to mention a tad of really bothering relativistic effects. More to that later.
So: We have a problem. The distances we are talking of are SO huge, that even the best propulsion system, including those who are just tested and somehow in the near future ready for use, are in no way efficient enough. Moon? Sure. But the moon is reaaaaally close. Distance: 1 lightsecond (the distance a lightbeam, photon, would travel during a second).
And thats just the moon. In no way sufficient. In around a billion years, life becomes a problem on earth, so our destiny is, long term, to colonise not just other planets in our solar system, but inevitably other solar systems. These are a tiny little bit further away. The next solar system (and we dont even know what is there) is a bit less than 5 lightyears away. If we have already not so few trouble getting to the moon and back without a monster of ressources we need....can you imagine what such a travel would mean as effort? Even if you would put that amount of ressources in (i guess the whole world would have to work together for free for a couple of decades), it would still be a real undertaking and, with current means, such a travel would take hundreds of years. One way.
Next problem: Relativity. "simultaneous" does not exist. But can be close. Every event is spread from the source with the speed of light. Example: Our sun would from one second to another become dark. the sun is around 8 lightminutes away. So if it happens now, right now there, the event would be by us realised 8 minutes later. It is not easy to syncronise therefore events apart.
Our current level of technology is very crude. Despite we invented computers and lasers, ion propulsion and tons of other stuff, our current knowledge about the nature of the things and (which is THE most important thing) our ability to manipulate our surroundings is very very limited, despite all progress we have done. There is still much much to learn about that. We call it science.
Edit:
There are more problems to us than just that. In our current economic system, we dont do research "by fun", we do it to expect a profit. Note that i didnt said "beneficial effect". We do it for profit. There are exceptions to it (base research), these are done by gov financed universities. The fast majority of current research is done by companies though, and there, only profit counts.
Which means, that our level of science research to the relevant parts to undertake such projects are neglected. We do a lot of research for example into "male performance enhancement", yet, compared to it, very little for improvement on propulsion systems. Stupid example, maybe, but you get the idea. Science is connected to each other, so we need also a better understanding to a load of other fields, for example materials. Alloys. Composites. Energy production (actual: Conversion. You cannot produce energy, only convert one energy form to another).
And much much more to say on all this...
Last edited by shining1977; 12-19-2012 at 04:26 AM.
12-19-2012
, 04:36 AM
Quote:
How to comprehend the age of the universe? The shortest time span I can grasp without effort is about one tenth of a second. The longest is about 100 years, a life time if long lived. Therefore I can somehow understand the number of tenths of seconds there are in 100 years, that's about 30 billion.
The age of the universe is about 13.7 billion years. That's in years about the number of tenths of seconds there are in 50 years. Will work on trying to comprehend that!
The key to the methods I have developed here with your help looks to be that you base the estimations on really well known parameters, and then do just one mental jump when scaling up or down. It feels like I could get accustomed to these easy processes and increase the understanding of sizes, distances and time. Hope you can too!
The age of the universe is about 13.7 billion years. That's in years about the number of tenths of seconds there are in 50 years. Will work on trying to comprehend that!
The key to the methods I have developed here with your help looks to be that you base the estimations on really well known parameters, and then do just one mental jump when scaling up or down. It feels like I could get accustomed to these easy processes and increase the understanding of sizes, distances and time. Hope you can too!
Same with time and distances. Get dettached from the "need" of getting the meaning, proportions, in your head and just deal with them, as they are
12-20-2012
, 03:34 AM
I think I have an excellent grasp of the scale of the universe. I would gladly share it, but I can't grasp the conversion from KM in the OP example to miles.
Sorry.
Sorry.
12-20-2012
, 05:20 PM
Quote:
So assume that you want to build the model such that the sun is as big as an apple, let’s say 10 cm, which would make earth about 1 mm (great we can actually see stuff 
). Then you have to put Alpha Centauri about 3000 km away, a bit less than the diameter of the moon. A model of our galaxy in that scale would have a diameter of about half the distance from the sun to the earth. And if you would add the Andromeda galaxy to your model it would have to go past Saturn.
). Then you have to put Alpha Centauri about 3000 km away, a bit less than the diameter of the moon. A model of our galaxy in that scale would have a diameter of about half the distance from the sun to the earth. And if you would add the Andromeda galaxy to your model it would have to go past Saturn.
Putting it this way (two apples, 3000km apart) helps to show how empty outer space really is.
11-16-2014
, 05:39 AM
