<p>Is <a href="https://en.wikipedia.org/wiki/Inflation_(cosmology)" rel="nofollow noreferrer">Cosmological inflation</a> still considered as hypothesis?
Is CMBR evidence not enough?</p>

CC BY-SA 3.0
2017-05-13T21:00:21.540Z
If this is possibly in reference to the [article published in Scientific American](https://www.scientificamerican.com/article/cosmic-inflation-theory-faces-challenges), it might be worthwhile to explore the [response from the protagonists](https://blogs.scientificamerican.com/observations/a-cosmic-controversy) too.
Dhruv Saxena
CC BY-SA 3.0
2017-05-14T07:58:34.150Z
This question is mostly semantic, stemming from the attempts of the education system to clearly distinguish "hypothesis" from "theory". I don't think an answer is possible as I don't think there is a clear separation.
James K
CC BY-SA 3.0
2017-05-15T00:01:14.113Z
@mikey I ain't capable enough to provide an accurate scientific account. However, to what I understand, think the essence of the antagonist argument is that because the universe appears to be fine tuned (ratios of dark energy and matter density - in nearly isotropic distribution - as evidenced by CMB), it should have been such from the beginning, rather than becoming fine tuned and flattening out due to Inflation, later (although Inflationary theory itself is fuzzy about Planck Era). So, per them, either Inflation is not needed at all, or that if it occurred then it wouldn't have ever stopped.
Dhruv Saxena
CC BY-SA 3.0
2017-05-15T00:02:14.797Z
It's also argued that Big Bang didn't result in Inflation; instead it was a Bounce from a previously collapsing universe. However, the issue _inflated_ because the article went on to call the Inflationary theory unscientific for some of its predictions (inflatons, gravitational waves, etc) being untestable. The theory has been verified greatly enough so far, but Big Bang grav waves etc. are beyond our detection capability atm. This led to Dr. Guth et al (33 physicists including 4 Nobel laureates) pitching strongly in favor of the credibility and testability of the theory in their reply.
Dhruv Saxena
CC BY-SA 3.0
2017-05-15T08:45:29.287Z
This is a comment rather than an answer because I too am not qualified. My understanding of what motivated the development of cosmic inflation as a concept was to solve what appeared to be a fine-tuning problem, the apparent uniformity of the CMBR. However, inflation as a concept has been fine-tuned (there are multiple versions of cosmic inflation), and each has its own fine-tuning problem. There are a number of physicists and cosmologists who neither accept nor reject the concept of cosmic inflation. They instead are on the fence, leaving it as a hypothesis rather than a theory.
David Hammen
<cosmological-inflation>
Is cosmic inflation still a hypothesis?
Kushal Madane
# Is cosmic inflation still a hypothesis?

(Asked by: username_0 on 2017-05-13)

Is [Cosmological inflation](https://en.wikipedia.org/wiki/Inflation_(cosmology)) still considered as hypothesis?
Is CMBR evidence not enough?

**Tags:** cosmological-inflation

> **Comments:**
> **username_1**: If this is possibly in reference to the [article published in Scientific American](https://www.scientificamerican.com/article/cosmic-inflation-theory-faces-challenges), it might be worthwhile to explore the [response from the protagonists](https://blogs.scientificamerican.com/observations/a-cosmic-controversy) too.  
> **username_2**: This question is mostly semantic, stemming from the attempts of the education system to clearly distinguish "hypothesis" from "theory". I don't think an answer is possible as I don't think there is a clear separation.  
> **username_1**: @mikey I ain't capable enough to provide an accurate scientific account. However, to what I understand, think the essence of the antagonist argument is that because the universe appears to be fine tuned (ratios of dark energy and matter density - in nearly isotropic distribution - as evidenced by CMB), it should have been such from the beginning, rather than becoming fine tuned and flattening out due to Inflation, later (although Inflationary theory itself is fuzzy about Planck Era). So, per them, either Inflation is not needed at all, or that if it occurred then it wouldn't have ever stopped.  
> **username_1**: It's also argued that Big Bang didn't result in Inflation; instead it was a Bounce from a previously collapsing universe. However, the issue _inflated_ because the article went on to call the Inflationary theory unscientific for some of its predictions (inflatons, gravitational waves, etc) being untestable. The theory has been verified greatly enough so far, but Big Bang grav waves etc. are beyond our detection capability atm. This led to Dr. Guth et al (33 physicists including 4 Nobel laureates) pitching strongly in favor of the credibility and testability of the theory in their reply.  
> **username_3**: This is a comment rather than an answer because I too am not qualified. My understanding of what motivated the development of cosmic inflation as a concept was to solve what appeared to be a fine-tuning problem, the apparent uniformity of the CMBR. However, inflation as a concept has been fine-tuned (there are multiple versions of cosmic inflation), and each has its own fine-tuning problem. There are a number of physicists and cosmologists who neither accept nor reject the concept of cosmic inflation. They instead are on the fence, leaving it as a hypothesis rather than a theory.  

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## 0 answers

