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Universal map - logarithmic scale(32 posts)

Universal map - logarithmic scalePdxMark
Jan 14, 2004 7:58 PM
There are no more reasons to be lost. There is now a map covering everything from the center of Earth to the edge of the Big Bang:

http://www.astro.princeton.edu/~mjuric/universe/all100.gif

OK, maybe just a slice of everything.

You can find us near the bottom of the map, at unit 1 on the right hand scale (units of Earth radius). Scroll up to the top to find the edge of the universe.

I can finally relate to the ignominy of our southern hemispheric friends living at the bottom of the world.

Here is more information about the map and its preparation.

http://www.astro.princeton.edu/~mjuric/universe/
What's the zone of avoidance? Is that what Kirk and companysn69
Jan 14, 2004 8:25 PM
had to breech to get out of the galaxy? Wait, no that looks like it's way the shyt out there.

Wacky stuff. Thanks for posting it.
Scott
Could be at the edge of the Milky Way disk at...PdxMark
Jan 14, 2004 9:47 PM
10^14 Earth radii. Dang, that sounds like a really far way away. I really like this visualization. It's the first time I could grasp the size of the universe. A logarithmic scale is something I can comprehend.

Hey, maybe we should twist this into a political rant about how logarithmic scales could show people current Federal deficits in terms of prices for cars, houses, 747s, skyscrapers, Hurricane Andrew, etc.!! Naww... I'm tired of the politcal battles here.
Most people have trouble with linear scales on graphs.dr hoo
Jan 15, 2004 9:45 AM
Log scales don't compute for most people, and they just see them as linear... missing the impact of the scale.
In Star Trek, did they ever leave the galaxy?DougSloan
Jan 15, 2004 10:15 AM
Seems to me that even at warp 12, whatever they did, you could never travel to another galaxy, assuming no wormhole type of thing. I can't recall, though, but did they ever travel to another galaxy?

Doug
I seem to recall one time. Some kindOldEdScott
Jan 15, 2004 10:19 AM
of hideous barrier they had to pass through? They'd been hijacked by a being from another galaxy who wanted to go home? Was going to redesign the Enterprise to make the trip?

Ah, these flashbacks.
distancesDougSloan
Jan 15, 2004 10:34 AM
The Enterprise could travel at maxiumum warp (almost) 10, and at that speed, it would take a full 6 months just to *cross* the Milky Way, and 10 years to reach the next nearest galaxy. http://www.gmoon.freeserve.co.uk/trek/warpspeed.html

As know, there is NO WAY Scotty could have sustained that pace for long, either!

Doug
Sloan Great Wall at 10^18 earth radii -- What's Doug been up to?Dale Brigham
Jan 15, 2004 8:48 AM
I thought he was "out there" at times, but did not know he went that far adrift from home.

What's your Great Wall made of, Doug? Old inner tubes? Discarded goo packets? We gots to know!

Dale
I bet it's painted celeste blue! nmsn69
Jan 15, 2004 9:01 AM
coolDougSloan
Jan 15, 2004 9:18 AM
What the heck is this "Sloan Great Wall?" Will I inherit it from some long lost great uncle? Can't wait to see the deed to that sucker.

Doug
Great walls are dense groupings of galaxies.dr hoo
Jan 15, 2004 9:43 AM
Something like 250,000 GALAXIES. And so if you inherit it, you better time it to avoid the estate tax.
Ford Galaxies? 250,000 of 'em? Man, Doug hit the jackpot!Dale Brigham
Jan 15, 2004 10:07 AM
Great cars! Classic V-8 Dearborn iron. Run for light-years and light-years.

Dale
"walls"DougSloan
Jan 15, 2004 10:16 AM
Funny how you'd call something a "wall" that is 99.999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999% empty space.

Come to think of it, though, I suppose a brick wall is, too.

Doug
If brick walls are mostly empty space, does that mean...dr hoo
Jan 15, 2004 10:30 AM
... that you can walk through them?

I ask that of my students when we talk about social constructionism. They want to know, if everything is definitions, and if physicists define it that way...

I tell them that OF COURSE you can walk through a brick wall if you are careful enough, because it is mostly empty space. You just have to believe. I then ask if anyone wants to bet I can't do it. I concentrate, close my eyes, wave my hands, then I walk through the brick wall.

Ah, fun with undergrads.
Teachings of Don Juan. nmOldEdScott
Jan 15, 2004 10:39 AM
Hippie.dr hoo
Jan 15, 2004 10:56 AM
Not that there is anything wrong with that.
well, you could, ifDougSloan
Jan 15, 2004 10:39 AM
the trick in getting through the brick wall is about the same as pushing two north ends of a magnet together, but with trillions of them at once, isn't it?
Ah, no. The lesson is about how words highlight...dr hoo
Jan 15, 2004 10:55 AM
... certain aspects of the world while tending to blind us to others.

By saying I can walk through the "wall" by slipping through the empty spaces, everyone focuses on the wall. The trick is to find the RIGHT empty space in the wall.

I am sure you can think of a large empty space in a wall, though you normally don't think of it as WALL. You have another word for it, and by applying that word (door), you will never see it as "empty space in a wall" or a "doorWAY". You will see it as a separate thing.

A similar thing is the "scavenger hunt" riddle. Someone knocks at your door at midnight, dressed in a tuxedo. They tell you they are on a scavenger hunt, and all they need to win is a 3x7 piece of wood, for which they will pay you $3000. Can you get the payment?

This works on students, who usually don't have a garage full of wood. But VERY few people say they will give the person the door. Doors are doors, so we tend to not see them as "pieces of wood".

Of course I sometimes get a kid who has WORKED, who will inform me of the EXACT dimensions of a standard door. That's fair, if I can be an a55hole, so can they.

Categories empower, categories restrain.
got itDougSloan
Jan 15, 2004 11:04 AM
Actually, there is no such thing as a 3x7 piece of wood. Maybe 3'x7'x2", though.

Yes, I was a philosophy major and English/linguistic minor. Took just enough science to be dangerous, though.

I was focusing on the similarity between the "Great Wall" and a brick wall, that is, that they are both mostly empty space. The primary difference is that the brick wall has different forces at work, keeping most things from passing through.

Doug
yeah, gravitational vs. weak nuclear forcesdr hoo
Jan 15, 2004 11:20 AM
I went to school on a physics scholarship, but the combination of quantum mechanics and finding out my scholarship was NOT major dependant led me down another path as a sophomore. Schrodiner's equations did me in. I could DO the math, but I lost my "feel" for physics at that point. And soc. was just so much more FUN.

I still like it, but only as a casual fan. If it ain't written in math, it's casual.
yes, all that math takes the fun out of it nmDougSloan
Jan 15, 2004 11:23 AM
Takes the Tao out of it too.OldEdScott
Jan 15, 2004 11:25 AM
I read 'prose physics' all the time. Better than drugs, in my view. Really gets you out of your head and into something Bigger.
Hawking is good at splainin it nmDougSloan
Jan 15, 2004 11:26 AM
I didn't mind the math.dr hoo
Jan 15, 2004 11:38 AM
I rather like math. Give me a nice catapult problem, or even pure math, and I don't mind. It was just that impossible things started to happen that I could not wrap my brain around.

Like a charged particle goes at an electrical barrier that it does not have enough energy to get through. But sometimes it gets through. Waaaahhhhh?!?!?!

The math and the things that the math described lost connection for me.
Math!53T
Jan 15, 2004 5:13 PM
You're talking about tunneling, and/or quantum well devices, a very important concept in semiconductor lasers, like the ones that run optical communications systems, like the one you are using to access the internet right now. Scary huh?

Anyway, brick wall walkers consider this: If you want to hand mix concrete, you must have gravel, sand, water and portland cement. You question: If you want one yard of concrete, how much gravel do you start with?
That's a trick question!dr hoo
Jan 15, 2004 7:12 PM
NO ONE wants to mix a yard of concrete by hand. Call a truck. That's a lot of material to shovel, much less MIX.

Given the "empty space between" theme, where the sand/water/cement would filter, it has to be more than one would think from the ratio of sand/cement/water/gravel. 1 yard would give way too thick a mix, and 1/2 a yard would give too loose a mix. Ok, at a rough guess I would say 3/4 of a yard of gravel.

My back hurts even thinking about it.
Very close but no cigar53T
Jan 17, 2004 10:26 AM
For one yard of concrete, start with one yard of gravel. BTW, if you take your time, use a long handled shovel mixing a full yard won't kill you. Just make sure you use it all, since you won't want to carry the left overs away!
That just doesn't sound right to me.dr hoo
Jan 17, 2004 2:15 PM
After scouring the web, I found this:

"For estimating purposes, you can make about 1 cubic yard of concrete with five 94-pound bags of cement, 14 cubic feet of sand, and 21 cubic feet of gravel. "

http://www.homestore.com/HomeGarden/HomeImprovement/HowTos/HowTos/CRHO_MixingConcreteOnSite.asp?poe=homestore

Now, isn't a yard = 27 cubic feet? 21/27=.78, which would put me pretty close.

In any case, if I need a yard +, I'm calling a truck.
As you go through life/make this your goalOldEdScott
Jan 15, 2004 11:15 AM
Watch the doughnut/not the hole.

--K Kesey
the trick is to reduce yourself to the size of an atom (nm)ColnagoFE
Jan 15, 2004 11:56 AM
11,243 galaxiesJS Haiku Shop
Jan 15, 2004 10:36 AM
give or take 238,757 or 238,758. ;)
That's what I get for using memory and not google. (nm)dr hoo
Jan 15, 2004 10:58 AM