inflation

[devrimci_kürt]

The total context shows that there was no big bang. The distance problem is an example. Physicists claim the universe is about 15 billion years old. When they look at a galaxy which is 15 billion light years away, they say they see it shortly after the universe began. How did it get that far away in such a short amount of time? If it traveled at the speed of light, it would have taken 15 billion years to get that far away from the earth in addition to the 15 billion years for the light to get to earth. It doesn't add up. One tenth the speed of light would be a more realistic velocity for matter to travel. It would then have taken 150 billion years to get that far from the earth.

 

this is not my idea...

Excerpt from Gary Novak

 

 

 

 

what do you think ?

Edited November 18, 2009 by devrimci_kürt

[Spyman]

I think you should STOP reading stuff that this "Gary Novak" writes...

(You where already told in another thread that he can't be trusted.)

 

 

The evidence for a Big Bang with an expanding Universe is overwhelming:

 

Big Bang

The Big Bang is the cosmological model of the initial conditions and subsequent development of the Universe that is supported by the most comprehensive and accurate explanations from current scientific evidence and observation.

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

 

Observational evidence

Theoretical cosmologists developing models of the universe have drawn upon a small number of reasonable assumptions in their work. These workings have led to models in which the metric expansion of space is a likely feature of the universe. Chief among the underlying principles that result in models including metric expansion as a feature are:

 

- the Cosmological Principle which demands that the universe looks the same way in all directions (isotropic) and has roughly the same smooth mixture of material (homogeneous).

- the Copernican Principle which demands that no place in the universe is preferred (that is, the universe has no "starting point").

 

Scientists have tested carefully whether these assumptions are valid and borne out by observation. Observational cosmologists have discovered evidence - very strong in some cases - that supports these assumptions, and as a result, metric expansion of space is considered by cosmologists to be an observed feature on the basis that although we cannot see it directly, scientists have tested the properties of the universe and observation provides compelling confirmation. Sources of this confidence and confirmation include:

 

- Hubble demonstrated that all galaxies and distant astronomical objects were moving away from us, as predicted by a universal expansion. Using the redshift of their electromagnetic spectra to determine the distance and speed of remote objects in space, he showed that all objects are moving away from us, and that their speed is proportional to their distance, a feature of metric expansion. Further studies have since shown the expansion to be extremely isotropic and homogeneous, that is, it does not seem to have a special point as a "center", but appears universal and independent of any fixed central point.

- In studies of large-scale structure of the cosmos taken from redshift surveys a so-called "End of Greatness" was discovered at the largest scales of the universe. Until these scales were surveyed, the universe appeared "lumpy" with clumps of galaxy clusters and superclusters and filaments which were anything but isotropic and homogeneous. This lumpiness disappears into a smooth distribution of galaxies at the largest scales in much the same way a Jackson Pollock painting looks lumpy close-up, but more regular as a whole.

- The isotropic distribution across the sky of distant gamma-ray bursts and supernovae is another confirmation of the Cosmological Principle.

- The Copernican Principle was not truly tested on a cosmological scale until measurements of the effects of the cosmic microwave background radiation on the dynamics of distant astrophysical systems were made. A group of astronomers at the European Southern Observatory noticed, by measuring the temperature of a distant intergalactic cloud in thermal equilibrium with the cosmic microwave background, that the radiation from the Big Bang was demonstrably warmer at earlier times. Uniform cooling of the cosmic microwave background over billions of years is explainable only if the universe is experiencing a metric expansion.

 

Taken together, the only theory which coherently explains these phenomena relies on space expanding through a change in metric. Interestingly, it was not until the discovery in the year 2000 of direct observational evidence for the changing temperature of the cosmic microwave background that more bizarre constructions could be ruled out. Until that time, it was based purely on an assumption that the universe did not behave as one with the Milky Way sitting at the middle of a fixed-metric with a universal explosion of galaxies in all directions (as seen in, for example, an early model proposed by Milne). Yet before this evidence, many rejected the Milne viewpoint based on the Mediocrity principle.

 

Additionally, scientists are confident that the theories which rely on the metric expansion of space are correct because they have passed the rigorous standards of the scientific method. In particular, when physics calculations are performed based upon the current theories (including metric expansion), they appear to give results and predictions which, in general, agree extremely closely with both astrophysical and particle physics observations. The spatial and temporal universality of physical laws was until very recently taken as a fundamental philosophical assumption that is now tested to the observational limits of time and space. This evidence is taken very seriously because the level of detail and the sheer quantity of measurements which the theories predict can be shown to precisely and accurately match visible reality. The level of precision is difficult to quantify, but is on the order of the precision seen in the physical constants that govern the physics of the universe.

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

 

 

About expansion and recessional velocity faster than light:

 

Nonetheless, popular literature often uses the expression "Doppler redshift" instead of "cosmological redshift" to describe the redshift of galaxies dominated by the expansion of spacetime, despite the fact that the redshift is not found using the relativistic Doppler equation. In particular, Doppler redshift is bound by special relativity; thus v > c is impossible while, in contrast, v > c is possible for cosmological redshift because the space which separates the objects (for example, a quasar from the Earth) can expand faster than the speed of light. More mathematically, the viewpoint that "distant galaxies are receding" and the viewpoint that "the space between galaxies is expanding" are related by changing coordinate systems. Expressing this precisely requires working with the mathematics of the Friedmann-Robertson-Walker metric.

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

 

The redshift z often is described as a redshift velocity, which is the recessional velocity that would produce the same redshift if it were caused by a linear Doppler effect (which, however, is not the case, as the shift is caused in part by a cosmological expansion of space, and because the velocities involved are too large to use a non-relativistic formula for Doppler shift). This redshift velocity can easily exceed the speed of light.

http://en.wikipedia.org/wiki/Hubble%27s_law

 

While special relativity constrains objects in the universe from moving faster than the speed of light with respect to each other, there is no such theoretical constraint when space itself is expanding. It is thus possible for two very distant objects to be moving away from each other at a speed greater than the speed of light (meaning that one cannot be observed from the other). The size of the observable universe could thus be smaller than the entire universe.

 

It is also possible for a distance to exceed the speed of light times the age of the universe, which means that light from one part of space generated near the beginning of the Universe might still be arriving at distant locations (hence the cosmic microwave background radiation). These details are a frequent source of confusion among amateurs and even professional physicists.

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

 

[EDIT] There is also several threads on this subject already in the forums, you can use the search function in the top meny row to find them and read more about it, or other stuff before asking.

Edited November 18, 2009 by Spyman

[devrimci_kürt]

I think you should STOP reading stuff that this "Gary Novak" writes...

.

 

you are right...

well, who is gary novak..

I don't know...only I saw on the internet..

[ajb]

you are right...

well, who is gary novak..

I don't know...only I saw on the internet..

 

You have to be careful when reading things on the internet, especially if you are not very familiar with the topics. If the website is part of a university website, then you can assume it is ok.

 

Other personal websites should be viewed much more carefully. I tend to look up the author(s) on the arXiv to see what they have published. Generally, I can tell if a webpage is rubbish pretty quickly. There is something in the way it is written.

 

Now, Gary Novak the "independent scientist" has published one article in biology. He does not appear to be an authority on cosmology.

[devrimci_kürt]

ok..

ALAN GUTH?

 

what do you think about his Inflationary theory?

[ajb]

Guth is to be trusted.

 

His original proposal of inflation has been refined and reworked many times over. It is now accepted in cosmology.

 

The standard model of cosmology is "Big Bang + Inflation".

 

Much of the generic features of inflation are know. The difficulty is in finding out peculiarities of specific models of the inflaton and seeing if they can be tested.

 

One great achievement of inflation is explaining galaxy seeding via quantum fluctuations in the inflaton field and the cosmic microwave background anisotropies.

 

A good review by Liddle, "AN INTRODUCTION TO COSMOLOGICAL INFLATION" can be found in "High Energy Physics and Cosmology", 1999, eds. A. Masiero, G. Senjanovic, and A. Smirnov. Online it can be found here.

 

(Again, Andrew Liddle can be trusted.)