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18 years 2 months ago #15939 by Larry Burford
[Patrick's article] "Currently, most astronomers agree that the value of the Hubble constant is about 71 kilometers per second per megaparsec (a megaparsec is 3.2 million light-years). If this value were smaller by 15 percent, then the universe would be older and bigger by this amount as well."

[Patrick] "Okay first, if you take 100 and reduce it by 15% you get 85. If you increase 85 by 15% it does NOT make 100!"

Units.

You are never going to understand any of this if you don't start comprehending (and using) units.

If you reduce 100 [km/sec/mpc] by 15%, you get 85 [km/sec/mpc].

Now, if you increase 85 [km/sec/mpc] by 15%, you do indeed not get 100 [km/sec/mpc]. But that is not what the article said.

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[Patrick's article] "Scientists now estimate the universe to be about 13.7 billion years old (a figure that has seemed firm since 2003, based on measurements of radiation leftover from the Big Bang) and about 156 billion light-years wide."

[Patrick] "If the universe were 13.7 billion years old and it is understood that nothing travels faster that light then wouldn't the universe be 13.7 billion light years wide? How is it that the universe could expand at 11.386861 times the speed of light?"

Since the BB is almost certainly wrong, an incorrect detail like this really doesn't matter. But there is historical value in trying to understand old theories. Part of the difference coms from the need to multiply by 2 (to convert a radius to a diameter). The rest probably comes from inflation (a theory-patch, used by some to solve the BB's matter distribution problems, that supposes a brief period of superluminal expansion just after the magical pop), or some other BB BS.

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I'll pass on the last bit. Besides, I don't really believe it.

Regards,
LB

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18 years 2 months ago #15940 by Patrick
Replied by Patrick on topic Reply from P
Notice what the article said Larry:
<b>"If this value were smaller by 15 percent, then the universe <u>would be older and bigger by this amount as well</u>."</b>
If the values were 15% smaller then my calculation would show that the universe is actually 17.64705% larger than previously beleived. Am I correct or incorrect?


(Larry)<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">Part of the difference comes from the need to multiply by 2 (to convert a radius to a diameter). <u> The rest probably comes from inflation </u> (a theory-patch, used by some to solve the BB's matter distribution problems, that supposes a brief period of superluminal expansion just after the magical pop), or some other BB BS.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
All of what you said is plain jibberish. Please help me understand how inflation could cause expansion at a rate faster than "C". The factor in the article is a factor of 11+. Even if you were to multiply by 2 you would still only get 27.4 billion light years wide. Where did the other 128.6 billion light years of size come from?

Where do people come up with these nonsense numbers?



Patrick[:)]

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18 years 2 months ago #9106 by Larry Burford
[Patrick] "If the values were 15% smaller then my calculation would show that the universe is actually 17.64705% larger than previously beleived. Am I correct or incorrect?"

Yes.

I suppose we could try breaking this down into smaller parts, and taking them one at a time.
That way I tell if we are talking about the same thing.

The article says "If this value were smaller by 15 percent ... "

It is not clear to me that you read this the same way I do. Please write down the value they are talking about, and then write down what it would be if reduced by 15%.

Regards,
LB

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18 years 2 months ago #16057 by tvanflandern
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Patrick</i>
<br />Where do people come up with these nonsense numbers?<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">You need to learn the actual theory instead of the popular simplifications used in the media.

In the Big Bang, galaxies do not move through space (except for small, local motions). Galaxies do not get farther apart because of any motion. Instead, they get farther apart because new space is being continually created and added between galaxies.

We are told to think of an expanding balloon with dimes taped to its surface to represent galaxies. The dimes don't move on the surface, but are always getting farther apart from all other dimes on the same surface as the balloon expands. This is supposed to be a 2-D analogy for what happens in 3-D in the Big Bang.

Since space can be added at any rate, and the galaxies aren't really moving much, there is no violation of the speed of light limit no matter how much space was added in the last 13.7 billion years. That is what "inflation" is all about -- adding lots of space without adding much motion.

But as Larry says, few of us give the BB any chance, so this entire discussion is simply about understanding a soon-to-be-history notion. -|Tom|-

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18 years 2 months ago #16058 by Patrick
Replied by Patrick on topic Reply from P
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"> It is not clear to me that you read this the same way I do. Please write down the value they are talking about, and then write down what it would be if reduced by 15%.

Regards,
LB
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">

The article says:
(SNIP)********************
<i>The finding, which will be detailed in an upcoming issue of Astrophysical Journal, suggests that the Hubble constant, a number that measures the expansion rate and age of the universe, <u>is actually 15 percent smaller</u> than other studies have found. </i> END SNIP*********

(SNIP)*******************
<i>Scientists now estimate the universe to be about 13.7 billion years old (a figure that has seemed firm since 2003, based on measurements of radiation leftover from the Big Bang) and about 156 billion light-years wide.

<b>The new finding implies that the universe is instead about 15.8 billion years old and about 180 billion light-years wide. </b></i>END SNIP************************

13.7 billion x 115% = 15.755 billion (15.8)
156 billion x 115% = 179.40 billion (180)

Okay Larry, here is where it might get a little difficult for you so pay really close attention.

The article is saying that current Hubble measurements are believed to be inaccurate by 15%, 15% smaller than previously believed.

Let's just say that you had a space with 1000 measurement units between two points A&B. Now, let's say it turns out that each unit is actually smaller by 15% than originally thought. Each unit is only 85% of originally size. Do you increase the size of each unit by 15% to compensate? Do you increase the number of units by 15% so that there are 1150 units between points A&B? What? What do you do? <b>According to the article</b> they simply increased the total number if units(YEARS & LIGHT YEARS) by 15%. What was 1000(.85units) is now 1150(.85units) which according to my calculations is still incorrect.

Notice that a 15% increase to a .85unit makes each unit 97.75 x 1000 units = 977.5 units. Now notice that a 15% increase to the number of .85units equals 1000 x 15% = 1150 x .85units = 977.5 units. According to my calculations it would be:
15 / 85 = 17.64705....% increase per unit or number of units.
1(.85unit) x 1.1764705 = 1 unit
1000(.85units) x 1.1764705 = 1176.4705 units.

So Larry, I guess my answer is that the numbers in the article, not that I agree with the article, should have been 16.12 billion years old (instead of 15.80) and 183.53 billion light years wide(instead of 180).

Comments?

Patrick[:)]

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18 years 2 months ago #9108 by Larry Burford
OK, I guess we will be going in a different direction.

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I can think of no reason to prefer the article's numbers over your numbers. Or vice versa. It's all based on an obsolete theory that doesn't correspond to reality.

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