

Fabric of Spacetime
Name: Oolon
Status: student
Grade: 912
Location: UT
Country: USA
Date: Winter 20122013
Question:
What does Einstein mean by "the fabric of space" ? I mean,he states that massive bodies can "bend" the "fabric of space" around them,but does the space has a fabric of some kind? Are there any particles that can help us explain gravity, rather than Einstein's theories? Because even though I very much admire Einstein,the idea of "space consists of some kind of fabric" just does not make sense to me.
Replies:
You need to understand that space is composed of three geometric variables, call those (X,Y,Z) and a time parameter, (t). Newton?s view of the Universe was that there were the three ?space? variables and an independent time variable (t). Einstein proposed that the time variable could not be ?extracted? or ?separated? from the space variables, so that a point in space was expressed by the four dimensional variable (X(t),Y(t), Z(t)). Now the math gets more complicated, but gravity enters into the equations.
What Einstein means by the ?fabric of space? is an analogy, not a literal woven fabric, like a woven blanket. It describes how the four dimensional variables change under the influence of gravity.
This ?explanation? necessarily requires some ?hand waving?, because to really understand the consequences requires a level of mathematical sophistication that most of us just do not have.
Vince Calder
Oolon
Einstein uses the phrase ?fabric of spacetime? as a visualization aid. Something to help understand his idea. There is no real ?fabric? of spacetime.
Sincere regards,
Mike Stewart
Hi Oolon,
Thanks for the question. From my understanding, Einstein means that space and time are linked, in what we call a 4vector. Space does not have a physical fabric like nylon, cotton, or polyester. The graviton is an elementary particle that has been proposed to explain the gravitational force between two objects. The graviton has not been observed experimentally.
I hope this helps. Please let me know if you have any more questions.
Thanks
Jeff Grell
Oolon,
The history of mathematics involves a great struggle to understand ?zero?. One and two were part of mathematics long before zero came to be used. The difficulty centered on thoughts such as, ?If it is nothing, then it cannot be something.? Now, zero is something that describes what you have when have nothing.
Space is something. Unfortunately, we do not have words within our language to describe just what it is. In many ways, we do not know just what it is. To be in the space within a jar is different from being in the space outside the jar. In some way, the space within the jar is not the space outside the jar. If both are nothing, then you cannot compare them.
Einstein?s use of ?the fabric of space? indicates some sort of pattern or structure. ?Fabric? indicates that the structure is flexible. This structure is what allows the universe to have a boundary. The universe is not just stars moving apart through emptiness. The space itself has a boundary, an end. We do not know what lies beyond this boundary because we cannot measure it. Our tools of measurement work within space and time. Space and time are within the universe. Space without end does not agree with the properties and observations at the levels of quantum physics and relativity.
Dr. Ken Mellendorf
Physics Instructor
Illinois Central College
Hi Oolon,
Einstein was in reference to the spacetime continuum. He likened it to a rubber sheet with a dense ball sitting on it, forming a depression. He surmised that the fabric was spacetime and mass had a way to bend that spacetime so that there was an attraction  gravity.
The hypothetical graviton, the Higgs Particle and/or the field from Higgs are theorized in attempts to answer the confusion of gravity. Such a particle helps greatly with the mathematics model(s) of a physical unification. A particle approximating the theorized size of Higgs was found last July at CERN.
I am excited by the July discovery, it is another piece of the Universe. How it fits in spacetime and in explaining how gravity works still awaits elucidation. A number of researchers are looking at the Higgs field as possibly being spacetime.
Very fascinating! Thank you for your interesting question!
Peter E. Hughes, Ph.D. Milford, NH
Oolon
Einstein uses the phrase "fabric of spacetime" as a visualization aid. Something to help understand his idea. There is no real "fabric" of spacetime.
Sincere regards,
Mike Stewart
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