Why do scientists believe

pattylou

...that time is a dimension, rather than a field?

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Locrian

Well, I never use the word "believe" in the same context as the words "time," "dimension," or "field," so where does that leave me?

I usually treat time as a dimension because that word better describes its mathematical context in formulae that are useful.

pattylou

he he - You know, I was going to change the wordking on that..... But it was my husband's question so I left it alone.

Can you give some examples (of formulae) or elaborate a bit more? I know nothing, I'm just trying to get an answer dear husband can sink his teeth into.

neurocomp2003

because time is used as a parameter for ideal system f(t)....and if t has a domain
apparently it becomes a dimension. and in our case spacetime dimension.

chronon

H. G. Well's explains why time is really no different from the other three dimensions in the first chapter of "The time machine"
http://etext.lib.virginia.edu/toc/modeng/public/WelTime.html

This point of view was greatly helped by Special Relativity, in particular Minkowski coining the notion of space-time, and showing that Lorentz transformations were the analogue of rotations in 3 dimensional space

Berislav

Actually, time can, in a way, be represented as a field. Through the use of space-like hypersurfaces, one can define a time translatation Killing field orthogonal to the hypersurface.

Dr.Brain

This is because time does not change/effect the spacetime , rather it is a part of it , time is affected by the fields , the effect of fields , rather i should say strong fields can even affect the biological-time . If time was a field , it would have a source and since time is everywhere , there would be so many sources , so the time due to first source could easily affect the time due to other sources . which is not the case.

BJ

pattylou

time as a field

BJ,

Thanks. This helps clarify a bit. Particularily the part about time not having many sources. I'll have to think about this some more.
The point of similarity between time and a field that strikes me is that time is not constant throughout spacetime. An object travelling through space doesn't experience the same time as another object.
The very big difference between a field and a dimension to me is that dimension implies the ability to move about. Can we do this with time? For example can we move backward? I think we've invented rules that prevent us from doing this. I would favor a model where the physics itself prevented it. A field would imply that you experience time, but that it may be of different strengths for different objects and observers. But the field wouldn't be negative, so you wouldn't be able to travel backward.
Is it necessarily a show-stopper for my idea if we don't know how many sources a hypothetical time-field has, or what the sources might be?
What if there is only one source? One source might lead to a detectable gradient of time. I'm not sure how would would detect that. Or it might not lead to a gradient if we were all equadistant from the source. An alternative is that there are nearly infinite sources.
Are there other difference between a field and a dimension that would lead to testable hypothesis?

Thanks

Mike (patty's husband)

Dr.Brain

But the field wouldn't be negative, so you wouldn't be able to travel backward.
There is no 'negative' field as such . Field is a vector quantity , a negative field would mean , a field having an opposite direction to the positive field.Its more like how we take the signs to be rather than fields having a sign of their own.

A field would imply that you experience time, but that it may be of different strengths for different objects and observers
Referring to the title of your post. Its not about what do scientists believe what time is , but more peculiar is how time wants itself to be.We define time as 'order of events' , slowing up of time implies 'slowing up of order of events' and vice versa in case of time-travel forwards.Does field repect 'order of events'? , Time has no strength as such but it has a linearity which changes with the view of the observer.

shyboy

Dr.Brain said:
There is no 'negative' field as such . .
Not always. Field can be a scalar quantity, like a potential electric or gravitational field.

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