
Gödel and the unreality of time - chesterfield
http://edwardfeser.blogspot.com/2018/05/godel-and-unreality-of-time.html
======
motohagiography
I once saw a fridge magnet that said "time is natures way of making sure
everything doesn't happen all at once," and it's stuck with me.

The concept of time not being "real," can be useful as an exercise for
modelling problems where to fully explore the problem space, you need to
decouple your solutions from needing them to occur in an order or sequence.

From an engineering perspective, "removing" time means you can model problems
abstractly by stepping back from a problem and asking, what are all possible
states of the mechanism, then which ones are we implementing, and finally, in
what order. This is different from the relatively stochastic approach most
people take of "given X, what is the necessary next step to get to desired
endstate."

More simply, as a tool, time helps us apprehend the states of a system by
reducing the scope of our perception of them to sets of serial, ordered
phenomena.

Whether it is "real," or an artifact of our perception is sort of immaterial
when you can choose to reason about things with it, or without it. A friend
once joked that math is what you get when you remove time from physics.

I look forward to the author's new book.

~~~
mcguire
If I remember correctly, the full form of that joke is that time is nature's
way of preventing everything from happening at once and space is nature's way
of preventing everything from happening in Cambridge.

~~~
gowld
That may be _a_ variant.

[https://en.wikiquote.org/wiki/John_Archibald_Wheeler](https://en.wikiquote.org/wiki/John_Archibald_Wheeler)

cites some old sources that are (probably) a few years older than the
Cambridge version:

[http://www.ggdc.net/maddison/Personal/Autobiog1994.pdf](http://www.ggdc.net/maddison/Personal/Autobiog1994.pdf)

says:

> As Dharma Kumar paraphrased Joan Robinson, "time is a device to prevent
> everything happening at once, space is a device to prevent it all happening
> in Cambridge".

------
Schiphol
Folks are asking about the practical import of time not passing---if indeed it
does not. I know of this rather substantial one: my fear of death, and I guess
that of other people too, depends on the notion that my own annihilation in
time, and that of everything I care about, is absolute and definitive.
Existence no longer has me as one of its inhabitants, and that's that.

This picture is in its turn grounded on a presentist theory of time (the idea
that only the present exists), or at least an A-theory of time (the idea that
the present is somehow special, in absolute terms.) Nothing like that is true
if time does not pass: all of the moments that make me and everything I care
about are still _there_ , occupying their own spacetime regions, eternal, in a
way.

Realizing this has helped me see death from a slightly different perspective.
It still sucks, but it no longer feels like the absolutely unaceptable deal I
used to think it was.

~~~
sime2009
"I do not fear death. I had been dead for billions and billions of years
before I was born, and had not suffered the slightest inconvenience from it."
\-- Mark Twain

~~~
dsubburam
Here's a different take, another thought experiment Re: death, from Sigmund
Freud, Reflections on War and Death:

“We cannot, indeed, imagine our own death; whenever we try to do so we find
that we survive ourselves as spectators. The school of psychoanalysis could
thus assert that at bottom no one believes in his own death, which amounts to
saying: in the unconscious every one of us is convinced of his immortality.”

[Edit: Frued->Freud]

~~~
danenania
I think this is an important consideration. A subjective observer can never be
‘dead’ from their own perspective. So we are left with something like Zeno’s
paradox. We can get closer and closer and closer to death, but we will never
reach the end. Could this lead to a form of eternal life? Your final living
moment, subdivided endlessly, could play out as entire additional lifetimes in
your experience.

~~~
StanislavPetrov
>A subjective observer can never be ‘dead’ from their own perspective.

As a former boxer who has been "knocked out", I have always speculated that
feeling is akin to what death would "feel like" (that is, nothing at all).
When you are knocked out (as aside from asleep) you have no experience. You
don't dream, you don't feel has though time has passed - you don't feel
anything. One second you are awake and aware and the next second you wake up
lying on the ground (or don't wake up at all, if you are dead). It feels like
an instant, no matter how long you actually been knocked out for. This makes
it different than sleeping and simply not remembering your dreams upon waking.

~~~
komali2
This may not be everyone's experience, but I have been "lucky" enough to be
choked out accidentally during some sparring sessions.

It doesn't always happen this way, but when it does it's insightful: I first
get a very strong sense of "Wrong," as my understanding of the laws of physics
vanish. If the choke has finished and I'm left standing but still going to
black out, I'll probably topple at this point as I misunderstand gravity and
forget about/lose control of my legs.

Enough of my ego will still be aware enough to have the thought "this is
embarrassing, I've fallen," but it fades quickly as I lose understanding of
why falling is bad, what embarrassment is, and what ground is. Then there will
be a fading out of visual input (auditory goes before anything else), with my
awareness quickly shrinking to a tiny ball of awareness, which visualizes
itself as a bright speck of light surrounded by nothing. Panic will still
exist and set in, as the speck loses subsystem after subsystem, not quite sure
what is being lost but knowing things are, and feeling an encroaching
blackness.

Eventually the only thing left is a feeble desire to not vanish, followed by
nothing.

This might actually happen every time I get choked out, but only the right
circumstances allow it to be "written" to memory.

It aligns with what friends have told me about near death experiences (heart
attacks, overdose).

~~~
hoosieree
I wonder how much this aligns with the parts of the physical brain associated
with those different parts of the consciousness (ego, understanding, fear,
sensory, autonomous nervous system), and when they start to be deprived of
oxygen. From the way you described it, it very much has the feel of going back
in time from "civilized person" to "lizard brain".

------
cousin_it
You can just as easily have a Newtonian space with time travel (roll up the
time coordinate in a circle by identifying T=0 with T=1). I think the same
trivial construction would work in GR, so you don't need mass, rotation, etc.
That doesn't seem to prove anything about the nature of time. Does anyone have
a copy of Gödel's article so we can see if the argument goes deeper?

~~~
nabla9
Of course it's must deeper than that.

[http://kurtgoedel.de/cms-83FO/wp-
content/uploads/2016/10/Goe...](http://kurtgoedel.de/cms-83FO/wp-
content/uploads/2016/10/Goedel.pdf)

It's a solution allowed by GTR, not a new trick definition. It belongs to the
family of 'dust solutions'. You arrange particles (can be as big as galaxies)
that move in certain way and you get time travel. Only other assumption is
nonzero cosmological constant.

You can't get time travel in Newtonian universe just by arranging objects in
it to move certain way.

In general, closed timelike curves are allowed in GTR. It's possible generate
them several different ways. Gödel just made super elegant one. What GTR
allows and what actually is allowed are different matters. Just like Newtons
equations break at some extremes, same probably happens to GTR.

~~~
gradschool
If two trains are heading toward each other on the same track, one way for
momentum to be conserved is if they pass through each other. Even though
that's not what we observe in the real universe, its existence as a
mathematical solution implies that mass is an illusion. How is this argument
different from Godel's?

------
amplexian
For those interested in the topic, I can't help but reccomend the book Gödel,
Escher, Bach: An Eternal Golden Braid by Douglas Hofstadter.

~~~
empath75
I’m fairly certain that this isn’t covered at all in that book.

~~~
Omnus
You are correct, it is not, and the book is not relevant in any way to the
article, aside from both containing references to the work of Gödel.

~~~
macintux
Presumably it would take you five years to figure that out though, by which
point you may have discovered new interests.

------
elie_CH
For French speaking folks, listen to this course by Bouveresse
[https://www.youtube.com/watch?v=0kCfgM0U3kw&list=PLOq4PLensL...](https://www.youtube.com/watch?v=0kCfgM0U3kw&list=PLOq4PLensLtk0r-ABh__OXOgwwfthUdIO&index=1)

------
romdev
"Time is an illusion. Lunchtime doubly so" \- Douglas Adams

~~~
cutler
First thing that came to mind when I read the title. Ctrl+F "lunch". You beat
me to it.

------
kkylin
For those curious, the paper (or at least a paper) on the subject:

[http://dx.doi.org/10.1103/RevModPhys.21.447](http://dx.doi.org/10.1103/RevModPhys.21.447)

------
yehohanan7
got reminded of the book "Siddhartha" by hermann hesse

"After listening to the river, Siddhartha’s biggest insight is that time is an
illusion and that life is not a continuum of events, but instead is
omnipresent. Eternity springs from the world’s unity. Understanding the past
and the future as part of the present is a major component of achieving
enlightenment."

------
leni536
OK, so tldr: _If you can 't define a partial ordering between events (ie.
"earlier than" as in A can cause B, "later than" as in A can be caused by B,
"same time" as in there can be no causal relationship between A and B), then
time as defined in B-theory can't exist._

So what? What are the consequences?

~~~
dschuetz
Nothing! It's fun thinking about it.

I think, he's trying to say that "time" is really not a _thing_ , but rather
our perception and understanding of time makes it a thing. What we should see
as time is actually some flow of causality. You cannot map "earlier/later
than" or "same time" to causal reality, those qualities only refer to time as
a scale, not as a natural occurrence of causality order. Or so I think.

~~~
hammock
In other words, time emerges from causality (and our observation of it), not
the other way around. Is that right?

------
crispyporkbites
Sipping espresso

Pause, muse on time's illusion

Work must resume, shame

~~~
lindenr
Off-topic but, was that supposed to be a haiku? I only count six syllables in
the second line.

~~~
crispyporkbites
oops fixed

