Is time linear?

First off you have to understand that no one knows what Time may be.
It's certainly nothing to do with clocks, atomic or of the wrist variety.

The brain has it's own internal clock that it electro-chemical in nature and consists of a small area in the brain that experiences a neurochemically regular reaction.
It ticks regularly if you will.
I'm trying to remember what the area is called. No matter.

That area can be made to speed up and slow down by various means so that the subject experiences time "passing" at different rates.
You've experienced this yourself...'time flies when you're having fun' etc...
Well those sayings are based in fact.
You can alter your subjective experience of time.

As for "objective" time.....
Well no one knows.
What actually is it that clocks are dividing up ?
They seem to be measuring something but no one knows what.
It's not like length.
You can point to an object with a real physical reality and say "that's one unit in length".
But time is abstract.
All you're doing is dividing up this something into successively smaller intervals.
In fact that's a major area of contention in quantum research : Does the notion of time have any meaning or is it merely the concept of the interval that has relevance ?

No one knows.
Yet.

So, to get back to your question.

Basically subjective time can be non-linear.
Objective time has no meaning but if you create a clock that ticks at regular intervals then you have linear time.
If you create a clock that ticks in a non-linear way then you have non-linear time.

It's a head wrecker isn't it ?

I believe time is linear. Direct or sine.

I know that to us time appears linear. It is often referred to as a stream. What if "objective time" were more like a pond?

Whatever floats your boat, Boss, although a pond is gonna serverely restrict the size of said boat . . .

Apparently, the faster you move, the slower time runs for you. I wish someone could explain that in language I can understand (maybe there isn't language that simple!)

Ocean?

Our love is like a ship on the ocean
We've been sailing with a cargo full of
Love and devotion . . .

So i'd like to know where
You got the notion . . .
Yeah, i'd like to know where
You got the notion . . .

Rock the boat
Don't rock the boar, Baby
Rock the boat
Don't tip the boat over . . .

Sniffle. . .

Thank you, Set.

That was so sweet.

I love you too.

Just don't get any ideas. . .

This has to do with Einstein's theories of Relativity and Space-Time. I can try to explain more if you'd like... ?

You're on!

I'll go along with that. If the language can be kept relatively primitive.

Ya mean like ugga bugga mooga booga?

Thanks, Chumly. Very informative and understandable.

I suppose I should have added: is time one directional?

Speculation about the nature of time is just that. Speculation.

You're talking 'bout time travel? In the real world, there are lot's of paradoxes in that worm can, but it's a popular theme of certain SF genres. I have read numerous SF stories with time travel of some sort as a premise.

Didn't want to use the word travel, but yes. The chaos that might result from tampering with the past seems to controvert its possibility. But does it?

Neologist,

Your question "is time linear" can be taken in several different ways. The mathematical term "linear" denotes that the relationship between two variables can be expressed in the form "y = Mx + B" where 'M' and 'B' are constants and 'y' and 'x' are variables. I assume to answer the question on of the variables would represent time... but what is the other variable?

A thing can't be "linear". It is the relationship between two variables that is linear.

Let me rephrase my issue. If I told you with authority that yes, time is linear.... what would this mean? (I am not saying this, I am just pointing out that the question is not well defined).

Wilso,

The basic phenomenon (explained in as simple a way as I know how) is this:

Imagine Two observers watching the same two "events" and measuring the amount of time that passes between the first event and the second one. Each one reports the amount of time they measured between the events. They give different answers. The answers are equally correct (based on their point of view), in fact there is no "correct" answer.

I'll say there appears to be less paradoxes with future time travel then past time travel and this link is very good as we have:

http://www.pbs.org/wgbh/nova/time/

Carl Sagan on Time Travel
Listen to the late astronomer and Pulitzer Prize-winning author's insightful and delightfully droll views on everything from wormholes ("very Alice in Wonderland") to the nature of time ("one of those concepts that is profoundly resistant to a simple definition"). (text and RealAudio)

Traveling Through Time
In this excerpt from his 1998 book Time: A Traveler's Guide, Clifford Pickover, an IBM researcher and science writer, declares that "time travel is possible." Find out why he is so sure.

Think Like Einstein (Hot Science)
Albert Einstein showed that space is curved, time is relative, and time travel is theoretically possible. Here, do a simple thought experiment and learn to think like the century's greatest scientist.

Timespeak
What you would call a time machine physicists term a "closed timelike curve." Steep yourself on the concepts and conjectures, the dialects and definitions that physicists rely on when musing about the possibility of time travel.