Dark Energy Part 1: Einstein-deSitter Cosmology

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Discussion Overview

This thread discusses the introduction of the cosmological constant ##\Lambda## into Einstein’s equations of general relativity, motivated by findings from the Supernova Cosmology Project. The focus is on Einstein-deSitter cosmology and its relation to dark energy and the accelerating expansion of the universe. The discussion also touches on the challenges of accessing and sharing content related to the topic.

Discussion Character

  • Exploratory
  • Technical explanation
  • Meta-discussion

Main Points Raised

  • One participant introduces the concept of the cosmological constant ##\Lambda## and its implications for the accelerating expansion of the universe, referencing the Nobel Prize-winning work related to distant supernovae.
  • Several participants inquire about methods to download or print the thread for offline study, expressing dissatisfaction with the print quality from their browsers.
  • Another participant offers to share their original file containing LaTeX equations, indicating a willingness to assist others in accessing the material.
  • There are discussions about the challenges of converting LaTeX formatted content into a readable PDF, with one participant expressing concern over potential errors in the conversion process.
  • One participant notes the absence of equation numbers and active links in the PDF rendering they reviewed, highlighting limitations in the shared resources.

Areas of Agreement / Disagreement

Participants generally agree on the challenges of accessing and sharing content related to the discussion. However, there is no consensus on the best method for downloading or printing the thread, as multiple approaches are suggested without a clear resolution.

Contextual Notes

Limitations include the dependence on browser capabilities for printing and the challenges of converting LaTeX to a readable format, which may affect the accessibility of the original content.

RUTA
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In this 3-part series, I want to motivate the (re)introduction of the cosmological constant ##\Lambda## into Einstein’s equations of general relativity (GR) per the Supernova Cosmology Project (SCP) Union2.1 type Ia supernova data. As you probably know, this discovery won Perlmutter, Schmitt, and Riess the 2011 Nobel Prize in Physics “for the discovery of the accelerating expansion of the Universe through observations of distant supernovae.” ##\Lambda## is referred to as “dark energy” and as we will see in Part 2 it leads to the accelerating expansion of the universe. In this Insight (Part 1 of the series), I will introduce Einstein-deSitter (EdS) cosmology. In Part 2, I will introduce ##\Lambda##CDM cosmology (essentially EdS + ##\Lambda##). In Part 3, I will introduce the notion of distance modulus in astronomy and fit the SCP Union2.1 type Ia supernova data (distance modulus versus...

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Is there some way to download threads like this, say to a pdf, so I can study them off-line? When I hit print in the Edge browser, I do not get a very good printout. Thanks.
 
exmarine said:
Is there some way to download threads like this, say to a pdf, so I can study them off-line? When I hit print in the Edge browser, I do not get a very good printout. Thanks.
Sorry, I would like to do the same, but there is no way I know. If there's only text, no LaTeX math, you can copy/paste.
 
Do you want my original file with the LaTeX equations?
 
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Yes please. And thanks!
 
I copied it into a Word document attached here.
 

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exmarine said:
Is there some way to download threads like this, say to a pdf, so I can study them off-line? When I hit print in the Edge browser, I do not get a very good printout. Thanks.
1. Install a PDF Printer like PrimoPDF
2. In the browser go File > Print ..., and choose PrimoPDF.

You have now created a PDF file.

You can use PDFSAM to split and merge PDF files.

Using Edge? Bin it and use Firefox!
 
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Ah thanks FRODO. That is basically what I am doing. I have a PDF printer installed, and regularly use FireFox as well as Edge. But that has always produced jumbled and garbled page headers and text, basically unreadable. RUTA kindly made his Word file available, but it had the equations and symbols in LaTeX format. I managed to get all of those changed into readable format and over into a PDF file. (Is there some way, addin, app, or whatever to make that easy to do?! It took me quite a while get the file readable.) I meant to post it up here in case anyone else would like to study it offline. But I didn’t want to do that without RUTA checking it and his approval, so I sent him a message to that effect. But he wasn’t interested, which really surprised me… Heck, I will attach the PDF to this now just in case. Sure hope I didn’t make any errors in translating the LaTeX!

PS. I wish all the insight authors would make PDF files of their work available.
 

Attachments

My apologies, I thought you wanted the LaTeX file. I assumed you wanted the LaTeX so you could manipulate it. If I knew you wanted a PDF (immutable) rendering, I would have sent something in final (permanent) form.
 
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exmarine said:
Ah thanks FRODO. That is basically what I am doing. I have a PDF printer installed, and regularly use FireFox as well as Edge. But that has always produced jumbled and garbled page headers and text, basically unreadable. RUTA kindly made his Word file available, but it had the equations and symbols in LaTeX format. I managed to get all of those changed into readable format and over into a PDF file. (Is there some way, addin, app, or whatever to make that easy to do?! It took me quite a while get the file readable.) I meant to post it up here in case anyone else would like to study it offline. But I didn’t want to do that without RUTA checking it and his approval, so I sent him a message to that effect. But he wasn’t interested, which really surprised me… Heck, I will attach the PDF to this now just in case. Sure hope I didn’t make any errors in translating the LaTeX!

PS. I wish all the insight authors would make PDF files of their work available.
I looked at this rendering and I don't see any mistakes in the equations. It's too bad the equation numbers don't appear and the links are not active.
 
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