@kilroy70said If I'm walking across a bridge that spans a river I will (in time) reach the other side.
Years ago I lived close enough to my job to get there walking. And this involved walking across a bridge that spanned a river. I didn't need to measure the bridge in order to get across, although I was able to estimate its length by how long it took to get across.
My main concern wa ...[text shortened]... that level, so I have to take it on faith that the quantum experts know what they're talking about.
If you don't care how big something is then you would have no need to define it with a number. So your example would not be useful in a conversation related to defining sizes.
If you WANTED to measure it, but lacked the tools to measure length (maybe your tape measure isn't long enough) the length as a number would be infinite.
@kilroy70said Sorry, I still don't get it.
I don't see how an ability to make measurements has any effect on whether something is finite or infinite. It seems to me the word "infinite" (as you are using it) is a placeholder.
If something can be measured after it couldn't be measured does this mean something "infinite" then becomes "finite"?
Yes.
(although not necessarily a placeholder. because you haven't measured it you don't know if measurement is possible)
@wildgrasssaid If you don't care how big something is then you would have no need to define it with a number. So your example would not be useful in a conversation related to defining sizes.
If you WANTED to measure it, but lacked the tools to measure length (maybe your tape measure isn't long enough) the length as a number would be infinite.
The only tool I used for measuring the length of the bridge I crossed when walking to work was time.
I consistently walked at a pace of 20 minutes per mile, so all I had to do for judging the distance was to look at my watch.
@Metal-Brain I think the singularity thing will be dealt with if and/or when we are able to conflate relativity with Quantum physics, right now it is square hole V round peg, some new genius has to suss out ways to combine those two physics into one overall package and I think when that happens they will find there is no real infinitely small singularity but a real solution involving real sizes, maybe planks length tiny but not an infinitely small singularity. It looks to me like it is just our physics and cosmology has not gotten to the bottom of it yet.
@bunnyknightsaid A single point must be something, therefore nothing would certainly be infinitely smaller than a single point.
If a singularity is the smallest something can be and still exist, and no numeric value can be found between that infinitely small object and zero (i.e. nothing) wouldn't that mean zero equals infinitely small?
@kilroy70said If a singularity is the smallest something can be and still exist, and no numeric value can be found between that infinitely small object and zero (i.e. nothing) wouldn't that mean zero equals infinitely small?
zero < ? < infinitely small
Well, let's assume the universe just popped into existence. What was there before? If it was nothing then the universe could have tunneled into nothing from who-knows-where and if that tunnel has a size, then that may be the smallest thing, yet still way bigger than nothing.
But what if that pre-universe nothing is not nothing, but something else? What if the new universe is just a symptom of something that caused it to erupt, sort of like a bubble on the soup erupts when the heat is just right?
And if that pre-universe 'something' exists, it would be impossible to study because it exists outside our universe, thus impossible to ever reach or measure.
@wildgrasssaid If you don't care how big something is then you would have no need to define it with a number. So your example would not be useful in a conversation related to defining sizes.
If you WANTED to measure it, but lacked the tools to measure length (maybe your tape measure isn't long enough) the length as a number would be infinite.
I don't believe there is any disagreement here. There can't be, because you and I have been talking about two different things.
Einstein explained the relationship between mass, energy and the speed of light. He wasn't referring to an unknown numerical value when he said it would take an infinite amount of energy to push an object (mass) to the speed of light. But even if you could do this, that object (after absorbing all of that energy) would obtain infinite mass.
And he wasn't explaining how (say a rocket ship) could reach the speed of light. He was illustrating the absurdity of thinking this could be done.
So I don't think the point he was making had anything to do with an unknown number. It had to do with the absurdity of an infinite amount of energy pushing an object to light speed, and causing said object to have infinite mass.
@Kilroy70 So far even the best we can do with known physics but undeveloped technology would get us to half c with some kind of fusion drive or anti matter rocket.
It might be possible to supplement that thrust with laser light, mega terawatt lasers....
@sonhousesaid @Kilroy70 So far even the best we can do with known physics but undeveloped technology would get us to half c with some kind of fusion drive or anti matter rocket.
It might be possible to supplement that thrust with laser light, mega terawatt lasers....
I prefer using an ion drive engine when traveling through space. I'm in no hurry, but there are times when a little extra oomph is needed. So I have four on the floor, overhead cams and nitrogen injectors, and a big fuzzy pair of 🎲 🎲 dice hanging over the steering wheel.
@kilroy70said I prefer using an ion drive engine when traveling through space. I'm in no hurry, but there are times when a little extra oomph is needed. So I have four on the floor, overhead cams and nitrogen injectors, and a big fuzzy pair of 🎲 🎲 dice hanging over the steering wheel.
Ah darn it, need to move the dice over a few inches... can't see 👀 where I'm going.
I think I caught a flu virus today. I ache, have a low level headache, no appetite, and I'm 🔥 hot.
Okay, that last one goes without saying. 🧔
@kilroy70said I prefer using an ion drive engine when traveling through space. I'm in no hurry, but there are times when a little extra oomph is needed.
I'd prefer the Epstein Drive. It's similar to an ion drive, but provides 7 g's instead of 0.007 g's.
@sonhousesaid @Kilroy70 So far even the best we can do with known physics but undeveloped technology would get us to half c with some kind of fusion drive or anti matter rocket.
Not really. We can get as close to c as we like. We just have to spend more time accelerating.