Food for thought - debunking some folk-science

[RollyShed]

I thought trytip's story was too good to miss. Is this acceptable?

[Schultz]

catweazel wrote:
In modern physics, quantum physics that is, not your clockwork universe Newtonian physics,...

You seem to be anti-Sir Isaac Newton (I noticed at least on other comment about him/his ideas). I'm curious as to why.
(I'm not a scientist so take it easy on me. )

[Spearmint2]

It seems logical to conclude that science fiction movies are indeed fictional.

So is quantum mechanics. Takes a lot of a certain faith to believe in it.

[all41]

Hi,
string?
maths have no domain here--even standard model formula gets routinely adjusted to fit our limited understanding.

[trytip]

I thought trytip's story was too good to miss. Is this acceptable?

before i get kicked off this forum for language AGAIN here's some more info on this paradox. it was first created as a short story

Robert A. Heinlein
" '—All You Zombies—' " is a science fiction short story by American writer Robert A. Heinlein. It was written in one day, July 11, 1958, and first published in the March 1959 issue of Fantasy and Science Fiction magazine after being rejected by Playboy. The story involves a number of paradoxes caused by time travel.

it was later adapted as a movie:

Predestination (2014)
For his final assignment, a top temporal agent must pursue the one criminal that has eluded him throughout time. The chase turns into a unique, surprising and mind-bending exploration of love, fate, identity and time travel taboos.

after watching this movie i'm left with more questions, but the movie pretty much stays on course with the short.
the main character is their own mother,father and child all at different stages of his/her life. i'm sure there are quite a few holes in this paradox, but do like the idea that this hasn't been explored in films, well besides Futurama animated movie Futurama: Bender's Big Score (2007) and a few of their tv epidodes.

a nice addition to these time travel films are Happy Death Day (2017) and it's sequel Happy Death Day 2U (2019) which are modern day groundhog day type films where time loops and alternate realities are subject.

as for Interstellar, i did not consider it to be a time travel movie at all. i never even considered giving it the Back to the Future criticism

[catweazel]

In a sense, yes, but then the observer isn't really observing anything other than himself. But in a sense no, because the internal state is partially caused by external reality. That's why you don't leave your hand on a hot stove.

I need to stop you right there. That an external reality exists is a mere assumption on your part, and nothing more. You do not have direct access to any reality other than your own internal reality. When you see something at a distance, say a tree, your brain is projecting a three-dimensional image that your consciousness focusses on. That image has been sent to the brain by a sense organ, it is a mediated image.

If you're going to spruik an 'external reality' then I'm going to have to ask you to prove that it exists.

[gm10]

to spruik

Just in case somebody else has to look it up:

spruik
/spruːk/
verb INFORMAL•AUSTRALIAN

• speak in public, especially to advertise a show.
  "men who spruik outside striptease joints"
• promote or publicize.
  "the company forked out $15 million to spruik its digital revolution"

Best thing I learned from this thread yet.

[dorsetUK]

If you're going to spruik an 'external reality' then I'm going to have to ask you to prove that it exists.

I can't, but I have to believe in an 'external reality' as otherwise I'd go stark raving crazy.

Our personal beliefs create a 'world' in which we can imagine that we're happy - or not - and mine allow me to imagine that I'm replying to someone who's half a world away.

Jon

PS. Dear Prof C Weazel, I'm still waiting for someone else to admit that 2 + 2 doesn't always equal 4 and that a triangle can have considerably less, or more, that 180 degrees.

[Pjotr]

If you're going to spruik an 'external reality' then I'm going to have to ask you to prove that it exists.

Take a hammer in your right hand and hit the index finger of your left hand with it. Hit it hard.

That should prove to you, once and for all, the existence of an external reality.

The fundamental problem of many philosophies is that they talk too much and adhere too much importance to words. Word play may be amusing to while away a long winter's evening, but it won't help you to deal with the undeniable external reality.

[catweazel]

If you're going to spruik an 'external reality' then I'm going to have to ask you to prove that it exists.

Take a hammer in your right hand and hit the index finger of your left hand with it. Hit it hard.

That should prove to you, once and for all, the existence of an external reality.

No, it doesn't. Take away the sense of touch and one feels nothing at all.

[Pjotr]

If you're going to spruik an 'external reality' then I'm going to have to ask you to prove that it exists.

Take a hammer in your right hand and hit the index finger of your left hand with it. Hit it hard.

That should prove to you, once and for all, the existence of an external reality.

No, it doesn't. Take away the sense of touch and one feels nothing at all.

Word play.... The finger will be damaged anyway, which should also be visible. Or should we take away sight as well, and claim that therefore nothing has happened?

[gm10]

Word play.... The finger will be damaged anyway, which should also be visible. Or should we take away sight as well, and claim that therefore nothing has happened?

The point is that all we know about is observed data, but how that ties into actual reality is one of the issues quantum theories struggle with.

[Pjotr]

Word play.... The finger will be damaged anyway, which should also be visible. Or should we take away sight as well, and claim that therefore nothing has happened?

The point is that all we know about is observed data, but how that ties into actual reality is one of the issues quantum theories struggle with.

OK, but the way that reality behaves in quantum theory, has no bearing at all on the strictly Newtonian reality level when dealing with hammers and fingers. It makes no sense to try to extrapolate quantum theory to our daily lives, because it has no effect on that hammer and that finger. When in the slightest doubt about that, feel free to apply the experiment I described on yourself.

[Hoser Rob]

It seems logical to conclude that science fiction movies are indeed fictional.

So is quantum mechanics. Takes a lot of a certain faith to believe in it.

Actually to really understand it you need math chops. The problem with QM is that you simply can't explain it in ordinary language. There's nothing indeterminate about it, it's one of the most determinate theories we have.

[Mage of Maple]

I need to stop you right there. That an external reality exists is a mere assumption on your part, and nothing more. You do not have direct access to any reality other than your own internal reality. When you see something at a distance, say a tree, your brain is projecting a three-dimensional image that your consciousness focusses on. That image has been sent to the brain by a sense organ, it is a mediated image.

If you're going to spruik an 'external reality' then I'm going to have to ask you to prove that it exists.

This is a silly detour. Ok, maybe everything is a figment of my imagination - I can't prove it isn't. But if that's all this is, it invalidates all meaningful discussion. We reasonably assume that our perceptions correspond to an external reality. We take that as a given as we go about our day (and our science experiments.) Your solipsism doesn't add to the conversation, it just derails it.

[Flemur]

His point was that conscious observers are not necessary. Besides, bacteria react to their environment, like humans do: what else does "observing" consist of? In that old cat-box thought experiment the cat, the geiger-counter, the box and the air in the box, etc, etc are all "observers" in that they react to the environment, and that's why, in the real world, someone could open the box and figure out that the cat died two hours before the human observed anything, by measuring the cat's body temperature, etc. That would be true even if a regular cat were replaced by an unconscious cat or by something like a chemical which reacts to the gas.

Wrong. Particles can interact with other particles without collapsing the wave function and destroying the interference pattern.

The world continues on whether or not people observe it because humans and their senses and instruments are not fundamentally different from the rest of the universe.

What constitutes a measurement? We don't know, but we do know that it is more complex they you claim.

I made no claims about measurement, I didn't even use the word.

[Flemur]

I need to stop you right there. That an external reality exists is a mere assumption on your part, and nothing more.

You just assumed I exist, but maybe you're imagining that you're just talking to yourself.

[Spearmint2]

and that a triangle can have considerably less, or more, that 180 degrees.

In 3-D space, one could argue that it does, such as 4x180.

[dorsetUK]

and that a triangle can have considerably less, or more, that 180 degrees.

In 3-D space, one could argue that it does, such as 4x180.

As 'space' may be flat even in 2-D space a triangle can still have more or less than 180 degrees, and does anyone actually know what 'shape' the universe is?

Jon

[rene]

[ ... ] and does anyone actually know what 'shape' the universe is?

Although fairly unexpected all current indications point to it being flat or very nearly flat. And that, many are sorry to say, means triangles have exactly or almost exactly 180 degree angle-sums...