  # dstebbins

Senior Members

412

## Posts posted by dstebbins

### Why is it called String THEORY?

String "theory" has yet to be even so much as tested, much less proven (and yes, I know a theory can never be proven, only disproven; when I say "proven," I mean done at least once with the expected results). At this point, String "theory" is nothing more than a glorified hypothesis, because if you can't verify it in a lab, it's not science. A hypothesis is what you expect to happen, but unlike a theory, it is only backed up with theoretical data and math. Hmmmm, theoretical data and math? Sounds a lot like superstrings, doesn't it?

Shouldn't string theory be more appropriately called String Hypothesis?

### lightspeed camera.

Einstein claimed and proved that it is impossible for an object of non-zero rest mass to reach the speed of light, because it will require infinite energy to get it there.

Does the same apply for camera framerates? In the unknown future, could a person with sufficient technological and scientific education and a sufficient budget create a cam corder that is 299,792,458 frames per second, so that a person can actually watch a light bulb luminate a room?

### criss-cross numbers puzzle.

^^^Exactly, for example, if I were using a 2x2 matrix, the numbers 14, 23, 12, and 43 would be arranded like this.

14

23

14 is row 1. 23 is row 2. 12 is column A, and 43 is column B. Get it?

### criss-cross numbers puzzle.

First verticle number is the number that goes vertically in the A column. Same with first horizontal, only it's row 1. Last columns and rows are I and 9, respectively. It looks like this:

A1 B C D E F G H I

2- - - - - - - - - -

3- - - - - - - - - -

4- - - - - - - - - -

5- - - - - - - - - -

6- - - - - - - - - -

7- - - - - - - - - -

8- - - - - - - - - -

9- - - - - - - - - -

Replace the dashes with a digit so that nine of the 18 numbers are horizontal and nine of them are vertical in a 9x9 matrix.

### criss-cross numbers puzzle.

512349652

124876251

210012201

123648520

601586310

474808785

511665579

243155817

386529906

615204101

515987632

552103492

518979642

122011148

741085290

968647954

987654321

625316623

Arrange these eighteen 9-digit numbers so that half of them are horizontal and half are vertical, so that every number is used once, no more no less. The numbers will criss-cross, so that digit A1 is both the first vertical number's first digit and the first horizontal number's first digit, and I9 is the same way, only replace "first" with "last."

This is all the help you will get from me. Help each other, do not expect to do it by yourself. This is like Sasuke, a.k.a. Ninja Warrior; a win for one is a win for everybody. Good luck.

Edit: Correction: I will help you in one scenario: If you have a question about the instructions, I will answer them. Other than that, you must rely on each other for assistance.

### What's the organ I'm thinking of?

I know if I see it in writing, I'll recognize it. It's the muscle that acts as a one-way door between the esophagus and the stomach. It relaxes to allow food in, but contracts when the food is in the stomach to keep you from puking it.

What's the name of this muscle?

### need help proving something

I'm training to be a professional wrestler right now. Earlier today, my trainer complained about the room we were in being "the hottest room on earth." I told him, "No, the hottest room on earth is in Great Britain. It's literally hotter than the center of the Sun."

After about thirty seconds of "Are you serious" "Yes I am" back and forth, he finally said "I don't believe it."

I know you guys know I'm right, so can you give me a credible link (meaning no wikipedia, more like a University) providing documentation of this room's existence so I can email it to him? I'd look it up myself, but I'd need the name of the room to do that, which I don't have. Thanks ahead of time.

### Loan payments.

Can I get the formula that that calculator uses?

Btw, that doesn't allow you to change the compounding frequency; it just allows you to change the payment frequency.

### interest-gaining investments

So in the equation in the top, right hand corner, what does P, APR, and Y stand for?

### Loan payments.

I have two questions about loans.

1. How do I figure the value of each monthly payment for a loan I take out, knowing only the principal (including origination fee), interest rate, frequency of interest, and number of monthly payments? All the equations I've seen also require how much I'm going to end up paying in the end, and I don't know that for my situation. I know this can be done because there's financial calculators on banks' websites that do it.

2. Suppose I have multiple loans that all go into effect at the same time, but they all have different interest rates. Is there a shorter way of finding the sum of the monthly payments without finding each individual one and tediously adding them together? For example, if I find the mean interest rate and the total initial debt, would that work for the equation in 1?

### infinite gravity

I'd like to see some documentation on this, because what I read in Stephen Hawking's book A Brief History of Time says the exact opposite.

### factorial of a decimal

When you perform the expression n! (read "n factorial"), you multiply all the positive integers between one and n. They have to be positive, so n>0, but they also have to be integers, so you would think that factorial of a decimal is impossible.

However, when I put it into my computer's calculator, I do get a real answer. For example, .01! = 0.99432585119150603713532988870511..., and 2.1! = 2.1976202783924770541835645379483..., so there must be a way to perform a factorial of a decimal.

What is it? How do you do that?

### infinite gravity

When a star experiences gravitational collapse, it goes down to a point of zero size, and its gravity becomes infinite. I can see this being explained in two ways:

1. In GR, density is factored into the equation for gravity, as opposed to the Newtonian theory of gravity, or

2. The laws of Thermodynamics state that if you compress an object while keeping its mass the same, it gets hotter, so if you compress it to zero size (aka infinite density), it becomes infinitely hot, and according to e=mc^2, infinite energy = infinite mass = infinite gravity.

Which is it?

### Is this correct?

I'm the one who put in that comparison between the event horizon and a treadmill. Does that sound correct to you? Even if it's not technically like a treadmill in every conceivable way, I think it's sufficient for non-physics major people to get a good visual picture of how the event horizon is.

### equation for GR

As I copy the equation from the Wikipedia article for GR, I get G_uv = [(8*pi*G)/c^4]T_uv. Underscores siginify subscripts, and u is the greek letter Myu. Hey, I don't know how to put it in HTML! Sue me!

I can infer what some of these variables mean. Pi is Archamedes' constant, G is the Gravitational constant, and c^4 is the speed of light to the fourth power.

What do the other variables mean?

### refrigerator magnets

You're talking about electrostatic charges, like you get with static electricity (where your hair raises up). Magnetism is somewhat different.

http://en.wikipedia.org/wiki/Magnetism

But aren't electricity and magentism essentially the same thing?

### interest-gaining investments

The standard formula for an interest-gaining investment (such as a certificate of deposit) is v=pit (end value equals pricipal times interest times time). However, that foruma only holds if the interest only piles once per year. If the interest piles multiple times per year, such as quarterly, then there's a complex formula where if the number if times the interest piles equals one, then it simplifies into v=pit, and if the interest piles continuously, then there's a REALLY weird formula that uses the constant e.

What are these formulas? It's been several months since I've taken that class, so I've long forgotten.

### refrigerator magnets

Refrigerator magnets stick to refrigerator doors (duh, common sense, eh?), so the fridge must have an opposite magnetic charge to a fridge magnet. One is positive, the other is negative.

But by that notion, two fridge magnets should both be the same charge, and thus should repel each other, yet they stick to each other. Why is that?

EDIT: Btw, I put this in Chemistry because I learned about positive and negative charges in Chemistry class. If this is in the wrong board, please quietly move it to the proper one.

### black hole singularities

I was just read through Stephen Hawking's best selling book A Brief History of Time, and he continuously made comments about how a star experiencing gravitational collapse would eventually collapse to form a point of infinite density.

Wait: Infinite density? If it's possible for a star to become infinitely dense, then it should also be possible for an object to accelerate to c, giving itself infinite mass. If infinity is obtainable in one way, then it must be obtainable in another.

The explanation for mass not becoming infinite, however, is that if energy is continually applied to it, it will go faster and faster, but its rate of acceleration, if you will, will start to go down as it approaches c, so if you graph an objects mass relative to its velocity on an xy coordinate grid, with the object's rest mass being at 1, then c will be an asymtope (spelling?).

So why can't we say the same about black hole singularities? Why can't we say that, as a star experiences gravitational collapse, it will get smaller and smaller at the rate of m=Xvt, where m is the mass of the star experiencing gravitational collapse, v is the volume of the star/black hole, t is the time that has elapsed since the gravitational collapse began, and X is the "singularity constant" if you will (I chose X because I like the letter X), with a unit of kg/(sm^3). By this theory, only after an infinite amount of time, which is never reached, does the volume equal zero, and density become infinite.

Now, I know what some of you are thinking. "That would mean the event horizon would continually expand because the gravity is increasing." Keep in mind that this is relativity we're talking about (it was relativity that invented the concept of black holes), and relativity provides for spacetime curvature/distortion. It's possible that, after a while, the gravity of the star/black hole becomes so powerful that spacetime is becoming distorted at the rate at which gravity is increasing, so relative to a person a safe distance from the event horizon, those two things exactly cancel each other. This particular fix might require a slight modification to Einstein's theory of gravity so that it becomes a little more powerful at black hole levels, but hey, scientific laws are being rewritten all the time, so this should be just a drop in the bucket for scientists.

I'm pretty sure this has been thought of before (black holes aren't one of those things that can be solved by a "why didn't I think of that" answer), so where am I going wrong?

### can't go faster than light.

So what do these variables stand for, and why do we prime them?

### can't go faster than light.

According to the laws of Relativity, matter and energy are equivalent and interchangable at the rate of e=mc^2. This means that as an object speeds up, thus increasing its kinetic energy, its mass also increases. If a 1kg object is stationary, it has a mass of exactly 1kg. However, if it is going at a [relative] speed of 2 m/s, then by the rule of e=.5mv^2, it has one joule of energy, and by the rule of e=mc^2, it thus has an extra 1/c^2 of mass. Not enough to worry about, but once you get to a velocity of c, the mass becomes infinite.

Wait: Mass becomes infinite?! What's Einstein's mathematical justification for that? Mathematically, infinity occurs when you divide by zero (e.g. a vertical line has an infinite slope because it's x rise over zero run, or at least so says my Math professor, from freakin' CHINA!); the only reason high school students are taught that you can't divide by zero is because it's more practical to say that for high school purposes, so where do you divide by zero here?

I'm not saying Einstein's wrong. Quite the opposite: I'm interested in understanding his point of view. My IQ is only 20 points under his, not to mention I have the same type of autism he had, so I feel I have a good shot and understanding this.

### definition of a planet

^^^And how do I do that?

### definition of a planet

Well, I see an edit link. Either you missed it, they've locked your ability to make edits, or I'm special. I dunno... maybe some combination of those. If I lost some of my editing privileges, then I lost them the moment I signed up.

Fine. Is there any way for me to prove that I'm right without giving you my username and password? Perhaps some way you can see exactly what I'm seeing without actually logging into my Wiki account?

×