# Hidden dimensions of string theory hiding in 4D spacetime?

1. Jun 8, 2009

### Spinnor

Hidden dimensions of string theory "hiding" in 4D spacetime?

Could the hidden dimensions of string theory be "hiding" in 4D spacetime?

Thank you for any thoughts.

2. Jun 8, 2009

### diazona

Re: Hidden dimensions of string theory "hiding" in 4D spacetime?

um... not sure what you mean by that...

3. Jun 9, 2009

### Spinnor

Re: Hidden dimensions of string theory "hiding" in 4D spacetime?

If spacetime stops looking like a continuum at the smallest scales would there then be "room" for the extra dimensions of string theory in spacetime?

4. Jun 9, 2009

### arivero

Re: Hidden dimensions of string theory "hiding" in 4D spacetime?

When I was younger, 20 years ago, I had a thought about the fermionic dimensions being similar to the tricks to pass from second to first degree in sets of differential equations. Just a dream, but it is other way to "hide" dimensions.

Now my current belief is that hidden dimensions are only a convenient notation for consistent Yang Mills Kaluza Klein interactions.

5. Jun 9, 2009

### DaveC426913

Re: Hidden dimensions of string theory "hiding" in 4D spacetime?

The idea is that they are curled up on themselves. In theory, if you looked closely enough at something, you could see those higher dimensions. In fact, we are moving through them as we speak. When you wave your arm, it moves through the x, y and z dimensions in addition to the others, but the others are so vanishingly small that your arm wraps around their extent many, many times over a distance much smaller than an atom, which is why it makes no noticeable impact on the progress of your arm.

Have you read of the ant-on-a-garden-hose analogy?

An ant walks along the length of a garden hose. The surface of the garden hose is 2 dimensional -100 yards long and 1 inch around. From one hundred yards away though, the garden hose is so narrow, it can only be viewed as a 1 dimensional line. The ant is seen as progressing along this dimension.

Now, instead of walking straight along the garden hose, the ant walks slanted; his path is a helix or spiral, wrapping around the hose every few inches. He is now travelling through the 2 dimensions of freedom that the garden hose allows (one of which is virtually unlimited, the other of which is very, very short).

From 100 yards distance, we cannot see the 2nd dimension that the ant is moving through nor are we able to measure a significant slowdown in his progress along the hose. In short, we have no way of detecting the 2nd dimension of the hose.

Last edited: Jun 9, 2009
6. Jun 9, 2009

### Naty1

Re: Hidden dimensions of string theory "hiding" in 4D spacetime?

Absolutely! Where else could they "hide"?? They have to be "connected" to our everyday dimensions, otherwise we'd never be able to detect them.

7. Jun 9, 2009

### DaveC426913

Re: Hidden dimensions of string theory "hiding" in 4D spacetime?

...which we can't - so there's no "have to" about it.

8. Jun 11, 2009

### Spinnor

Re: Hidden dimensions of string theory "hiding" in 4D spacetime?

The physics of the Universe seems to require extra dimensions. Could these extra dimensions simply be extra degrees of freedom of "something" really small that lives in 4D spacetime? Something small and just complex enough to have extra degrees of freedom which require these extra dimensions. I have no problem with extra unseen dimensions but do we need them?