Ask Ethan #84: Where did light first come from? (Synopsis)

“Light thinks it travels faster than anything but it is wrong. No matter how fast light travels, it finds the darkness has always got there first, and is waiting for it.” -Terry Pratchett

If you want, you can imagine back in the Universe to a time before it looked anything like ours did. Before there was life, before there were planets, galaxies, stars, or even neutral atoms. Yet going back even to those times, there was still light, and there were still photons.

Image credit: the Cosmic Microwave Background of Penzias and Wilson, via http://astro.kizix.org/decouverte-du-17-mars-2014-sur-le-big-bang-decryptage/. Image credit: the Cosmic Microwave Background of Penzias and Wilson, via http://astro.kizix.org/decouverte-du-17-mars-2014-sur-le-big-bang-decry….

Sure, we can tell a story of how matter and antimatter annihilated away, leaving us awash in a sea of radiation, but what about that first "stuff" that existed in our Universe? Where did that come from? Surely, the Universe wasn't just born with it, like some a priori initial condition? There has to be a cause for it, right?

Images credit: E. Siegel. Images credit: E. Siegel.

Well, there is, but it might not be where you think. Come find out where the Universe's first light came from on this week's Ask Ethan!

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What causes the “weak spots” in the blocks?

By Ragtag Media (not verified) on 17 Apr 2015 #permalink

@1: this is flaw in Ethan's analogy. There is a lot of energy contained in inflation: when it stops, that energy has to go somewhere. It goes into photons, the same way it goes into photons when an excited electron reaches a ground state or an excited nucleus converts to a lower energy state.

This requires you think of the pre-inflationary state of whatever as being in an excited or metastable state. AIUI, Ethan is saying that. How you interpret that is up to you.

Perhaps (and I'm waxing philosophic here) a better way to think about it is as a QM requirement that something from nothing requires all the energy etc. of the somethnigs to net balance to zero (giving you net nothing from nothing). Inflation is a push on space; when it stops, maybe QM rules means this earlier inflationary period causally produces net forces such as gravity and things such as photons to appear in order to balance it. In this understanding, it may not be as valuable to think of one causing the other as it is to think of solving two sides of a conservation equation: if you know what the mv^2 (with vectors) of the inflationary side of the universe is, you can calculate what the mv^2 (with vectors) of the post-inflationary side of the universe must be.

It is impossible to state where light first came from and to figure out what first existed before light. Asking where did the "first stuff" that existed in our galaxy come from results in a never ending cycle of questions and theories. Yes, the Universe was not just born with it, however trying to figure out what caused light to first appear then begs the question - "What caused that which caused light to first appear?" and these questions continue to cycle.
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So we can never be sure what first existed in the universe and where that came from?

I still believe that there is a definitive beginning yet we are just not able to find this beginning point until our technology is more advanced

I disagree with Terry’s opinion. If darkness “moves” faster than light, why do we have an equation to find the speed of light and not of darkness. My logic tells me that if darkness “moves” faster than light, darkness should be more important. Yet we use the speed of LIGHT to solve quite a few problems in Science. How would you know if there was light before there was living creatures? 15130992

Another question about the analogy. If the blocks are space, what corresponds to the bowling ball that causes the collapse?

I disagree with Terry’s opinion. If darkness “moves” faster than light, why do we have an equation to find the speed of light and not of darkness.

For the same reason we don't have the mass of a hole.

Darkness is the absence of light, not the presence of dark.

Terry Pratchett would be immensely saddened that his efforts to lampoon privatives being reified and treated as real things was so easily ignored.

"So we can never be sure what first existed in the universe and where that came from?"

You can't be sure the sun will rise tomorrow.

You can't be sure you are real, or anyone else.

But you can be "sure" in the colloquial sense. Please refrain from using words in a specific sense with the intent to confuse their meaning.

"what corresponds to the bowling ball that causes the collapse?"

Nothing.

The bowling ball is not the thing in the analogy. The stretch in the fabric is the thing.

When the sphere developed the medium to which particles started move on, photons where one of primarily particles to move on this medium.We know that when electron goes to ground state they do emit light as form heat or light,this can prove that electron of some atom in that medium lost energy. .

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By Seromo Podile (not verified) on 18 Apr 2015 #permalink

What came before light? What a question. But we can never be just quite sure of what or how it happened. How and what was first in this universe. Trying to discover more only leads to another unanswered question.

By Mia (15127444) (not verified) on 18 Apr 2015 #permalink

How did light originate? One mystery that we will try and uncover or discover, and explaining it with another mystery.

Darkness can't move. Its physically impossible. Because darkness is in essence the absence of light.

This argument is the same as the chicken and the egg argument so no definitive proof can be given.

By Stephan 15033067 (not verified) on 18 Apr 2015 #permalink

i strongly disagree with Ethan because there is no scientific discover that can produce darkness but we can produce light.i think darkness doesn't travel it is just there already so we need light to see through darkness.

By Sinon Mohavia(… (not verified) on 18 Apr 2015 #permalink

Sometimes we must also understand that some questions are not answerable. This question of "where did the light come from" is like asking "what existed before nothing?" Science should only be used for our own benefit not by complicating our way of thinking. The student who asked professor Fabio Gozo is not a serious science student.

By Chiangjieh ARM… (not verified) on 18 Apr 2015 #permalink

The student did not ask professor Fabio Gozo an interesting question at all. This question is not answerable even though Ethan is trying his best to give an explanation.

By Chiangjieh ARM… (not verified) on 18 Apr 2015 #permalink

i do agree with Ethan ideas cause darkness has been already there so we need light to be able to see through darkness during the day we need light from the sun and night we use artificial light.so we can come with the conclusion that darkness travel faster than light.

By sinon Mohavia(… (not verified) on 18 Apr 2015 #permalink

Such question will lead us back to God. It makes sense to say that the universe was created out of nothing.

If photons being small packets of light that come from the radiation of sunlight and there wasn't sunlight before in the universe what was the source of the light in the universe that was present. What evidence is there that proves that there was light in the universe way before it became what it is in the present day.

By Lungile 15324959 (not verified) on 18 Apr 2015 #permalink

The mentioned quote above possess depth thinking in ones mind because darkness doesn't move it is still and the only thing traveling is light so it is true that darkness is always first than light

By Nate 16234959 (not verified) on 18 Apr 2015 #permalink

If photons being small packets of light and come from sunlight radiation, where did the light that was present before in the universe come from before the universe became what it is now.Also where is the proof that there was light in the universe before it became the way it is now because I can't seem to think of any other source of light.

By Lungile 15324959 (not verified) on 18 Apr 2015 #permalink

@ Ethan, reading your posts is always a refreshing exercise. You make science interesting with a sense of humour to keep the mind alert. Thank you.

By TRK Ngaka u15103634 (not verified) on 18 Apr 2015 #permalink

It is quite difficult for us to comprehend to such a degree as to imagine what is in this vast universe at this present time but to examine what has occurred in the past is complexity to the highest degree. This has made me ponder on the significance of how we perceive how fast light actually travels if the darkness is already there. Brilliant Ethan! What has intrigued me is that how can you be sure that photons did exist prior to our creation if there is no substantial evidence but only proposed theories?
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By Taahir Moolla (not verified) on 18 Apr 2015 #permalink

Not to bring religion into sensitive matters but how can you be s sure that photons existed if no evidence is present?

By Adam Jameson (not verified) on 18 Apr 2015 #permalink

regardless, Ethan your posts are an eye opener and I appreciate your efforts and wish you the best to allow us the opportunity to keep on learning from you!

Darkness is the absence of light, so when there is light there is no darkness, but as soon as light vanishes darkness appears.which simply means that light travels at the speed of the darkness.

By Aubrey Hopjane (not verified) on 18 Apr 2015 #permalink

Darkness is the absence of light, so when there is light there is no darkness, but as soon as light vanishes darkness appears.which simply means that light travels at the speed of the darkness.15026338

By Aubrey Hopjane (not verified) on 18 Apr 2015 #permalink

I feel that light is faster then the darkness and science has proven it.

Our universe had nothing but the hydrogen element on its own at first. As it cooled down, the electrons and protons within the hydrogen element began to pair up resulting in atoms containing mostly the hydrogen element. The temperature got low for other elements to form, and the cosmos entered a dark age. Subsequently, stars began to shine. This proves that darkness existed before light and therefore might be faster than light. 15058239

Im split right down the middle and can't decide on whether darkness or light travels faster as i assumed the later did but I'm open to more research.

By Pranav Naidoo (not verified) on 18 Apr 2015 #permalink

Our universe had nothing but the hydrogen element on its own at first. As the temperature, the electrons and protons within the hydrogen element began to pair up resulting in atoms containing mostly the hydrogen element. The temperature got low for other elements to form, and the cosmos entered a dark age. Subsequently, stars began to shine. This proves that darkness existed before light and therefore might be faster than light. 15058230

Really important thing is that there is no answer, thats what I think.
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Really think that science is empirical in nature and needs proof so it is debatable to which one we can conclude on. I'm not really sure but would love to know.
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Photons did exist before our existence. All photons are are variations in the electric field and that didn't require humans or, initially anyway, matter.

Nowadays most of the photons created are created by matter moving. But that's mostly because there's not enough energy density to make photons appear without matter being a stepping stone.

And do not use loaded words like "creation". It's a bit like using the word "God" in a Christian church when you're talking about Ganesh. People will get the wrong idea of what you're on about.

one thing that most scientists fail to realize is that, because of the fact that light from the nearest star to our solar-system actually take 4.3 years to reach this solar-system which means we are only looking at some from the past

By cornelius(u15213201) (not verified) on 18 Apr 2015 #permalink

The Big Bang theory is a topic that is constantly discussed in the science world. What's very odd is that i never really gave much thought to where the first light came from. As with any theory in science, there is a few holes but I enjoyed the authors views and explanation on the topic. It is definitely a topic I want to do more research on.
What I found Interesting is the relationship between light and darkness. Light always overcomes darkness which may make a person conclude that light is faster than darkness.

By Thanyani Masha… (not verified) on 18 Apr 2015 #permalink

Goes to show that science can't prove everything. Sometimes the answers are right in front of us. The story of creation is the only answer. Genesis 1:1 In the beginning God created the heavens and the earth.
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By Merlin van Wyk (not verified) on 18 Apr 2015 #permalink

The light we see today is In fact light from years ago so when first light appeared ,we assume it also only appeared years later so surely a " swoosh" before the actual " Bang" is what sound would have occurred ? I disagree with the statement saying that darkness should be the speed calculated in today's science instead of light, because how can you calculate speed of darkness. Darkness doesn't travel, it is just there.If there was no light then everything would be dark,thus its lack of light makes it dark.

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The article is very interesting, and very debatable. I cant fault the science, however the big bang theory is still a theory as it cannot be proven. The article addresses where the first light came from however it does not address where the first, highly energetic, particles came from. Although it is difficult to believe that something simply always existed the alternative, that something originated from nothing, is completely incomprehensible.

By Guy Schiever u… (not verified) on 18 Apr 2015 #permalink

Its amazing to know that darkness travels faster than light whereas we have always known light would be the fastest thing.this shows that the scientific community is growing.u14231591

By Nhlamulo Hobyane (not verified) on 18 Apr 2015 #permalink

This is a question that is beyond our scope i`d say. none of us where ever there nor is there any evidence of what was there except for what is written in Bible.

By KSanyatwe (not verified) on 19 Apr 2015 #permalink

Am interested in the sequel to this, whether Ethan will convince me otherwise :)
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By KSanyatwe (not verified) on 19 Apr 2015 #permalink

however the big bang theory is still a theory as it cannot be proven

That's a theory. Can you prove it?

Nope.

however it does not address where the first, highly energetic, particles came from.

Well, given that the point wasn't to address that, what's your problem? You don't address the issue of nuclear proliferation. Can I complain of that?

I disagree with the fact that darkness travels faster than light as light is a medium and darkness is absence of light. We have no know value for the speed of darkness, if there is even such a thing, but we do however have a known value for the speed of light. Energy is never created nor distorted, light energy was therefore transformed from another energy form.
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By Zahlia Stacey (not verified) on 19 Apr 2015 #permalink

There is no such thing as dark, moron.

Therefore it doesn't move.

Read up on who Terry Pratchett is.

I do believe that many of these are astroturfers building up a list credibility for paid spamming elsewhere.

"Genesis 1:1 "

What about Genesis 2? With a completely different creation myth. It's like both stories were made up and put into a book of stories!

Darkness is inversely proportional to light that is a logical fact. About what really goes fast than the other i really have got no idea.

By Nkosconer (not verified) on 19 Apr 2015 #permalink

Haha, I was wondering what was going on! Reading through a swath of nonsensical comments.

By Stirling Bekervac (not verified) on 19 Apr 2015 #permalink

The numerable 'spam' comments are merely students doing an assignment choosing the shortest article to comment on. Think nothing of it. I can guarantee that most read the first line (which was terry pratchett) and ran with it. Interesting synopsis, I am eager to read more!

By Hamish Craze (… (not verified) on 19 Apr 2015 #permalink

Strange

By Striling Bekavac (not verified) on 19 Apr 2015 #permalink

Very Strange

By Hamish Craze (… (not verified) on 19 Apr 2015 #permalink

"...shortly before the Big Bang..." ... Before ... ?

By Gabriel Schulhof (not verified) on 19 Apr 2015 #permalink

As a matter on interest and also somewhat similar to the current topic at hand. Is there a new explanation floating around as to why there is so much more matter than antimatter?

By Hamish Craze (… (not verified) on 19 Apr 2015 #permalink

The discovery of light is indeed one of the greatest scientific discoveries up to date...this is astonoshing and awesome?

By CLITON ROCKY(1… (not verified) on 19 Apr 2015 #permalink

"students doing an assignment choosing the shortest article to comment on"

Why?

What damn course has as coursework "spam stupid shit on a blog"???

Spammer School 101?

"except for what is written in Bible."

Which is less accurate than The Thomas Covenant Chronicles.

Or were you there when god dictated the bible?

I believe that laws of science are not enough to explain the existence of the universe and its complexity if the darkness is faster than light that means the light travels on darkness so what does darkness on what is it that is before darkness

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i meant what does the darkness travels on?

"if the darkness is faster than light"

darkness isn't a thing. it doesn't move.
dumbass.

I understand what "Wow" is trying to say even if it is a bit inappropriate. Light is a combination of particles and waves as everyone surely knows. Darkness is simply the absence of light and not a form of something on it's own. What Terry was trying to say is that there was a time without light (darkness) and there will someday be a time without light. This does not refer to darkness as a moving object but a state of absence of light.
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By Dalton Moller (not verified) on 20 Apr 2015 #permalink

"What Terry was trying to say is that there was a time without light (darkness) and there will someday be a time without light"

No, Terry Pratchett was writing a comedic fantasy fiction where he lampoons, among other things, the silly ideas people have turning abstract things, especially reified absences and, in this highly magical and silly world, make them real and play about with them.

Read up on Diskworld:

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

So no, you are incorrect. PLEASE attempt even cursory investigation before pontificating on something.

@54 Gabriel Schulhof

Before the BB, there was a period of inflation, as we are informed. So, yes, BEFORE is apt.

What Terry was trying to say is that there was a time without light (darkness) and there will someday be a time without light.

del(p)*del(x)>=hbar/2. del(p)*del(x) /= 0, ever, so no, there was no time without stuff, at least not in any definable space where the rules of QM held sway.

So matter is frozen light.
I'm down with that.

By Ragtag Media (not verified) on 05 Aug 2015 #permalink