Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: jeffreyH on 21/04/2018 13:26:09

Title: Can we tell we are in a box in freefall?
Post by: jeffreyH on 21/04/2018 13:26:09

In a box falling freely it is said there is no experiment that can determine we are in motion. If we are in a very large box we could use rubber balls thrown at the walls. Gravity will change the kinetic energy of the balls. It will slow this moving away from the source. This change in inertial motion will indicate freefall towards the source of the gravitational field.

Title: Re: Can we tell we are in a box in freefall?
Post by: PmbPhy on 21/04/2018 14:59:34

Quote from: jeffreyH on 21/04/2018 13:26:09

In a box falling freely it is said there is no experiment that can determine we are in motion. If we are in a very large box we could use rubber balls thrown at the walls. Gravity will change the kinetic energy of the balls. It will slow this moving away from the source. This change in inertial motion will indicate freefall towards the source of the gravitational field.

It depends on stature if the field. If the field is uniform then no. Otherwise yes. Simply bring a gradiometer with you and you can make that determination.

I wrote a paper about this. I recommend reading it. See:

Einstein's gravitational fiel
http://xxx.lanl.gov/abs/physics/0204044

I strongly recommend reading it. It's full of Einstein's thoughts on the subject at hand.

Title: Re: Can we tell we are in a box in freefall?
Post by: jeffreyH on 21/04/2018 18:58:09

I was interested in "The effect of gravitation on electromagnetic phenomena" but in the positive and negative z direction. I am particularly interested in this with respect to special relativity. I haven't finished reading the whole article yet. Thanks Pete. This is much appreciated.

Title: Re: Can we tell we are in a box in freefall?
Post by: PmbPhy on 22/04/2018 16:25:18

Quote from: jeffreyH on 21/04/2018 18:58:09

I was interested in "The effect of gravitation on electromagnetic phenomena" but in the positive and negative z direction. I am particularly interested in this with respect to special relativity. I haven't finished reading the whole article yet. Thanks Pete. This is much appreciated.

You're most welcome, Jeff. Gravity distorts the field lines of an EM field. Is that what yuan meant?