Are Singularities Real?

In this video I explain what singularities are in mathematics, what different types of singularities there are, and that, most importantly, singularities do not necessarily come with anything being infinite. I then talk about singularities that appear in physics, such as pinch off points of droplets and black hole singularities and discuss whether singularities are real.

You can join the chat about this video today (Sat, Dec 12) at 12PM EST / 6PM CET here

#science #physics #mathematics

0:00 Intro
0:17 Singularities in Mathematics
2:59 Singularities in Physics
6:18 The Technological "Singularity"
7:08 Summary
7:35 Sponsor Message

[KeithCooper-Albuquerque]

This is the singular-most interesting video on singularities I've seen in awhile. Thanks Sabine!

[StCharlos]

I like the way how calm she said “You will die before you reach the singularity.”

[TK__]

I'vevalways been troubled by physicists talking about the black hole singularity seemingly being real. They never differentiate between the mathematical singularity and what really is at the center of a black hole.

A neutron star has volume so why wouldn't a black hole have volume at its center. Well the answer comes back, "because the math says so". And while you say we don't know because we can't observe whats inside a black hole, my mind cannot conceive of nothing at its canter. The black hole consumes mass, so there must be mass there, and must have volume.

I realize I am trying to visualize something the we can't definatevly know. But its one of those things that hurts this amateur scientists brain.

Thank you Sabine for teaching us to question the status quo. Your videos often show me another perspective, in addition to probing deeper into topics than most science videos on youtube. You are a credit to your profession.

[das_it_mane]

Crazy how in 8 mins, you explain this stuff more clearly than hour long lectures

[brucerogermorgan]

Thank you Sabine, I enjoyed this a lot. I find I have to really concentrate to understand this, and I still miss some of it, but it's a pure joy to listen to someone who really knows what they're talking about, and can express it so clearly. I now find that, at 71, I can still learn. This is a good thing! Thanks again.

[DJ_Force]

I love how you explain physics without trying to amplify the gee-wiz factor. It's refreshing to see a scientist that doesn't worship science.

[svenglueckspilz]

2:57 Fun fact: It is only really understandable in complex analysis (complex as in complex numbers), why this type of singularity is called an "essential singularity". In the real numbers, the function can be continued pretty smoothly (continuously, differentiably, ...), but if one allows z to be a complex number, then in any arbitrarily small circle around 0 (minus the 0, which can not be inserted into the function), the function exp(-1/z^2) takes on every complex value with the exception of possibly one complex number according to the "Great Picard Theorem". So it really goes crazy. On the other hand, the function (exp(z) - 1) / z has a "removable singularity" in 0, it can be continued to a complex differentiable function (also called holomorphic), because (exp(z) - 1) / z = (1 + z + z^2/2 + ... - 1)/z = (z + z^2/2 + ...)/z = 1 + z/2 + ... which tends to 1 as z approaches 0.

[chris_thornborrow]

I remain skeptical on the possibility of a singularity being discovered in nature, and if it were, I'd look very closely at the instrument of measure. Great video as always Sabine.

[odomobo]

Sabine, thank you for making the world a smarter place! Excellent video as always

[adamcandler]

I love this lady. No bias. No agenda. No preconceived notions. Just straight data and science.

[acampoverdeify]

I like that she explains things in such a way, that we can actually understand them. It's like she's not trying to waste our time.

[williammathews]

Incredible clarity of thought. Thank you Sabine !!

[johnstonewall]

Dr. Hossenfelder, many thanks for this video, and indeed all of your videos. They introduce me to aspects of the universe I had little idea of. I am in my 8th decade so your career should last long after I have passed away. May I wish you all success in your researches.

[rmehta]

Brilliantly explained. I wish I had teachers like you when I was in school. Thanks Sabine. It is not too late for me to understand the concepts.

[siddharthadasgupta]

Wishing you a very merry Christmas and a happy new year in advance Sabine 🎉☄️✨💫

[chrisdoyle]

Hi Sabine, I will put it down to coinesidence that you chose to do Singularities this week because last week you covered infinity.I'm glad you chose to cover this topic this week see next post, I enjoy your videos very much as they really challenge my theoritical work.

[pushkargautam]

I love your videos since they are so professional.

[williamschacht]

Excellente! There's so much good stuff to think about here.

[RomanMSlo]

I was updating Youtube application in Google Play while watching this video. At 5:29 the screen went black and the application restarted. For a while, I was genuinely thinking that this is some kind of intended illustration of what happens in singularity. The speech was perfectly aligned: "There's just <dark screen>". Just wanted to share to you all... 😀

[juancachelo]

The analogy with the drop of water is very useful. Thanks for the videos