Thread: The Universe.

Many scientists talk about how our universe has 4 dimensions of space-time; the 3 physical dimensions we see, and time, our fourth dimension. This is a theory I don't understand and personally think it is majorly flawed and illogical, since these same astrophysisists then talk about the theory of how the gravity of the planets, stars, and everything else in space creates a warping effect in the "fabric of space-time". This warping is not something visible to the naked eye, so it is not in the 3 dimensions we percieve, and it is also not time itself being warped, so it isn't in any of the 4 dimensions talked of. This means that for this warping to exist wouldn't there have to be at least five dimensions? I am just wondering what you think of this, and how many dimensions you believe space has. Also, for those who know what the string theory is, I am wondering what your thoughts are on that, as I know of it, but don't really get it.

Our universe is supposed to have 14 dimensions. Also, time is a dimension that we see, just not in an infinitely short instant. If you are seeing anything for more than an infinitely small moment, you are seeing time.

I am not sure about string theory. I think a lot of quantum physics will be disproven later. I don't understand how matter could be made up of energy when it seems that energy depends on matter. It seems to make more sense that matter is infinitely complex. But we will learn more in upcoming decades.

Originally Posted by Universal

Our universe is supposed to have 14 dimensions. Also, time is a dimension that we see, just not in an infinitely short instant. If you are seeing anything for more than an infinitely small moment, you are seeing time.

I am not sure about string theory. I think a lot of quantum physics will be disproven later. I don't understand how matter could be made up of energy when it seems that energy depends on matter. It seems to make more sense that matter is infinitely complex. But we will learn more in upcoming decades.
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^What he said^

The universe supposedly has 14 or something dimensions. I used to sort of understand it when I was reading Stephen Hawking, but a lot of the explanation has escaped me now. I, too, also have my doubts about string theory. Personally, I think there's no such thing as "matter" per se. Rather, I think that, at the basic level, certain properties simply exist and certain points of space time. So, discrete rather than continuous matter. But, meh, that's just my view.

Originally Posted by Universal

Our universe is supposed to have 14 dimensions. [/b]

Woops. Make that 11. Although some say 14, the majority of theoretical physicists seem to be saying 11.

I've tried to read someof stephen hawkings theories. A breif history of time is a good starter, i never could get past the first 5 chapters, i think ive read them 3 times and it still hasnt completely clicked. I do however like his theory on travel through space in long sistances by bending space.

Originally Posted by TheNocturnalGent

I've tried to read someof stephen hawkings theories. A breif history of time is a good starter, i never could get past the first 5 chapters, i think ive read them 3 times and it still hasnt completely clicked. I do however like his theory on travel through space in long sistances by bending space.
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Yeah, you NEED to get the illustrated versions of a brief history, and universe in a nutshell. The pictures really help. I own both.

And Symbiotic Entity: No, I can't list them. It's a really complex theory, yoiu sort of have to read, I'd suggest Hawking, to understand (or come close to understanding) what the hell all this multi-dimensional stuff is all about.

First off, I am so happy I found this topic, it has been a personal hobby of mine for a while now.

I can say that Hawking hasn't come out with much recently and frankly his brief history of time is outdated. I would suggest Brian Greene. He is the new guy in town. He has two titles out that i know of: The Elegant Universe and The Fabric of the Cosmos.

The Elegant universe deals primarily with Super String theory and M-theory while Fabric of the cosmos deals more with what is space and what is time? he goes through the history of human understanding from pre-newtonian physics through modern theories.

As for matter and energy, to me is not a question at all of wether or not they exist. Plainly, there is existence (or else what are we in?). Matter and Energy are just labels to the ideas of what is. And all of physics deals with the relationships within these ideas based on observations that we as humans can either directly of inderectly perceive.

There really is no seperation between matter and energy. They are one and the same expressed in different forms. This was shown by Einstein in his famous E = mc ^ 2 equation. Any amount of mass (the m in the equation) can be expressed as energy and vice versa. So matter is energy and energy is matter, they are really the same thing and it is of these two things that the universe is composed of.

On the ideas of time travel, I know of a few. One is very concrete and has been proven. Basically for any piece of energy or matter, there is a finite amount that one can be experiencing as time and as velocity (speed). You can never exceed or go lower than this combined limit of travel through space and travel through time. What this means is that the faster you travel through space, the slower you will travel through time to keep the balance of this combined velocity limit. The absolute limit is the speed of light. If you were to travel at the speed of light, all of your combined velocity limit will be in travel through space, so there would be no travel through time at all. So the 'time travel' idea here is that if you were to go into space and travel at a significant portion of the speed of light, you would age less than people that stayed on the earth and were moving at a very slower rate. You could then come back to earth after traveling for 10 years (from your perspective) and find that everyone has aged by 500 years.

As for the seeing the warping of the 3 (11) dimensions, it is not really visible to the naked eye. But then again, can you really say that you are 'seeing' the dimensions at all? or are we all just moving through them, interacting with them and are very much integrated with them. To see them with the naked eye, you would have to be outside the dimensions which as far as I know isn't possible ;P But there are many inderect ways to see this warping (curving) effect. Take for instance light reaching us from a distant star (not the sun). It has been seen that the wavelengths from these some of these stars changes in a periodic fashion. This is because those light rays get bent and curved from a nearby planet or another nearby star. THis curving is due to those planet's or stars masses. That mass causes a curving in the space-time fabric. And it is this curving that is (at least as we know it now) gravity.

String theory in a nutshell is a new theory that explains what the most basic constituent of matter (and therefor also energy) is. This question was originally brought up by the greeks when they thought: if you keep splitting an object in half, then in half again and again etc etc, what is it that becomes uncuttable?
For a long time it was thought to be atoms. Then we split those apart and found quarks, gluons and all the other basic particles that have been found. But what if these particles could be cut? the question continues. String theory is an idea that the smallest particle, the smallest peice of matter or energy could be a small vibrating string. THis string could be open, or a closed loop or many other possibilities. And that it is the vibrational pattern of these strings that give rise to the different particles that we know of now. The faster and more energetic a string vibrates, the more energy it has and so therefor gives rise to a heavier particle.

As for my own thoughts on quantum theory: I don't really think that they will be disproven and discarded as quantum theory is very real, has been tested and for some parts of it verified. All theories go through changes and reworkings as our understandings of the theory deepens. I think that if string thoery is shown to be on the right track of things, that quantum theory will not be discarded. The beauty of string theory is that it would unite quantum mechanics and general relativity under a more elegant and overarching theory that takes into account the behaviors found by each theory.


This is getting to be a long post so I will stop here. I would be interested to see what you guys think of all this and to talk about some more questions.

Could you list them? This sounds pretty interesting, but I'm skeptical.

I'll be the odd one here.
I say time is NOT a dimension. It's just a measurement to an idea.
The idea is true and all.
Basically, if you go faster than light, then you travel in the past.
It all has to do with that cool stuff.
I'm in 10th grade. Give me credit you little 8th grader. (just kidding.)
And mainly.. Time is not physical. Where as the 3 that we live in are.
Which makes me not believe it's a dimension.

Polarift...
A physicist (spelling?) said that they have a photograph of an object being at two places at the same time, it was about that double slit experiment. The one about the electron gun, particles or waves? Any ideas? Thanks for the information. Here is a video, I know it looks cartoney, but you'll get over it

Originally Posted by Bonsay

Polarift...
A physicist (spelling?) said that they have a photograph of an object being at two places at the same time, it was about that double slit experiment. The one about the electron gun, particles or waves? Any ideas? Thanks for the information.
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You're referring to Quantum Entanglement in which two or more objects have to be described with reference to each other, even though the individual objects may be spatially separated.

Ok, well..... Entanglement and the double slit experiment are 2 different things.

The double slit experiment is what revealed the particle wave duality of light and of all matter. The video above shows exactly what it is. When light passes through 2 slits at the same time, instead of having two bands appear based on the ideas of particle physics, there is an interference pattern. THis pattern can be viewed at home with a small pan of water and a make-shift wall with tow slits. The pattern you would see when creating a wace towards those slits in the water would be the same. This implies that light would be a wave.

And yet, we know that light comes in very discreet packets called photons. The smallest amount of light you can have is one photon and all light comes in integer multiples of one photon. The really interesting thing about the experiment is when they lowered the intensity of the 'light shooter' and let it run longer through the double slit. They slowed it down to shoot one photon at a time. With this setup, you would expect to see just two slits on the observing screen. But even with one photon at a time, the interference pattern is still observed. What gives?

It is now thought that on this quantum scale of things, matter has a probability wave associated with it. That is, each particle has a probability of being here or there. And it is this probability wave that in essence travels through the slits and gets interefernce patterns. (This gets wierd and in depth, I just got done with my classes for the day so I am a little tired, if you want more from this let me know.)

Entanglement is when 2 seemingly separate particles can influence one another over large distances instantaneously. Usually nothing can travel faster than the speed of light, and this includes information itself. Yet with entanglement, soemthing happens that seems to not even take spatial separation into consideration. When doing experiments with these entangled particles, tests done on one has shown immediate response from the associated 'sister' particle over 100 kilometers away. It was as if the two particles were still one and the same. And that is a good side note, in order for entanglement to occur, the particles must be very specially prepared (I am not sure how) such that a 'father' particle can be split and still retain all of the orginal properties.

Here I will leave with an interesting idea: At the beginning of the universe, everything, all matter, all energy was one and the same, uniform throghout. THen through expansion and quantum fluctuations we see all the differences we see now. But if we started all uniformly and as the same, then could not the entire universe be entangled? What would this mean? is every action, thought, movement... any influence at all instantaneously affecting something or everything else in the universe?

I don't agree with the 3-demensions stuff for sure. I say that matter is 1 demension. The time-field that can be bend (like by huge objects such as planets) the second demension.

Well, you have a point there with matter being only the first and only in the first dimension. Again, according to the new string theroy, all of the strings, all matter and energy that is composed in the universe is only in one dimension. Somehow (and I don't understand this one bit) physicists are saying that closed loops of these strings are only one dimensional. I really don't see how something in a loop form, with spatial extent in horizontal and vertical can only be in one dimension.

Hmmm...I think I've stumped myself creating this topic. I don't start to get half of what's being said here. I saw this show on the string theory on Nova once, and at that time sort of got it, but now I really don't remember. Pretty interesting stuff. I have heard though about the entanglement double-split thingy, but overall this is out of my league. Maybe a couple years and I'll get it better. And I thought I was smart Anyways, I remember the string theory making sense, and I believe that a lot of the quantum stuff won't be disproven, as quantum physics is so weird and confusing, anything could be true.

Well, I don't really know what to say from there. I'll give my bit, and some extra questions.

Firstly, has anyone read 'Hyperspace'? That book is fantastic yet insane! I like it. It has some very interesting facts and theories. There are ten dimensions, but it doesn't list each one. It says that the forth and fifth dimensions are of space-time, and any other higher dimensions are part of space too. Often throughout the book, it describes the inability to visualize higher dimensions, and so provides examples in terms of a 2D human, or Flatlander (who inhabits a flatland, is flat, and thinks flat). It also talks of spiritual beings existing in higher dimensions such as the forth and fifth dimensions.

All theories are believed to be simpler, when we consider higher and more dimensions. The universal theory of everything is 'supposed' to be beautiful and simple. So with all of these dimensions, scientists believe that they all interweb together to create a simple answer for creation and existance. Sorry if that sounds vague, I read the book a while ago.


There are some things I don't understand/or forgotten:

I ask those who know a lot about this stuff.

As an example, why does a train look compressed if it is travelling at the speed of light?

If 1 Dimension is just Length, can we see it? If it has no hieght, how can we see its thickness?

What is a Cosmological Constant?