Deep dive into the known forces 

More deep dives please. RU-vid is saturated with surface level treatments of science, so these are gold!

More deep-dives please. I never even realized that the top quark doesn't live long enough to feel the strong force.

Scientist: Yo, gravity. You the weakest force! Gravity: Come say that to my event horizon.

This is a really nice balance of, "whooboy, it's actually a lot more complicated than you've realized" and "let's explain what's going in a simple, approachable way." Solid programming, would love to see more like it.

RU-vid is full of videos which are ankle-deep into particle physics, but the ones which go into intricate details and describe smaller topics in detail are rare. I would opt for having these kind of videos every once in a while, they are greatly appreciated!

The demand for more deep dives clearly restores our faith in humanity and physics. The deeper the better.

Deeper dives! You guys are one of the few channels with talent qualified to explain these concepts in more detail. Almost any science journalism channel can cover the broad concepts, and I feel it would be a waste of your expertise to rehash it. In particular this video was excellent in clarifying my understanding of forces, and I've watched countless videos on the subject (as well as read several texts on it). For example, I had no idea that to escape the strong force, particles actually change into others which aren't affected by its influence. That is a concept I've not encountered before, and I appreciate it!

Deep dives! It helps to satisfy the 'but why' questions we have been asking from childhood. Also it's great to understand the limits of what we know, why we have reached those limits, and what's next.

The shallow videos are a great introduction, but the deep dive ones are much more thought provoking. If possible, keep producing both, as both are valuable to different audiences.

More deep dives, please. Your delivery makes it so I can follow further down the rabbit hole than I otherwise could.

4:50 One should mention that for _macroscopic_ objects, the negative and positive charges are usually almost exactly balanced, leaving only a _very_ small net charge in total. Hence for macroscopic objects, the ratio of charge to mass is ___much___ smaller than for electrons or protons, and hence the force of gravity is usually more important than the electrostatic force. (That's the point which all proponents of the "electric universe" conveniently ignore.)

I don't know anywhere else on RU-vid where I can hear advanced level physics topics explained in such an easy to understand style. It's what keeps me coming back to this channel. There are plenty of other channels that offer surface level overviews.

Absolutely more deep dives, please. How about a deep(er) drive into asymptotic freedom, which you briefly touch on here. Good stuff!

Finally a video where there's no BS about "universe borrowing energy for a shortest period of time" but the (slightly) more accurate description of the force carrier having a small enough mass. Kudos!

Yes, please Dr. Lincoln, a deeper dive into the weak and strong forces would be great! Keep up the great work!

Deep dives please! Deeper and crazy deep helps me to know what I need to study next.

Your intuitive exploration of uncharted territory provides a fresh and exciting perspective on quantum physics. Bring it! 💥

More deep dives! Thank you!

I love your dives into the "actual" causes everyday phenomenon (light bending, light slowing down, magnetism, etc.)!

I don't hold any qualifications in QM or any in maths and physics, but I find most RU-vid videos to be too basic; a little more depth is excellent! Your videos are at the perfect level for me, simple enough to (usually) grasp but complex enough to make me think. Thank you!

More deep dives - loved the explanation for the weak force

More deep dives. Love this host. Great explanations. Good energy.

Ah, another channel i can watch at 3am about physics while understanding absolutely nothing. Best way to fall asleep. You will make a fine addition to my collection

I love the deep dive! More of these, please!!

Great video, and YES PLEASE to more deep dives - there are already plenty of other videos without this level of depth. Thank you for doing these - the channel is terrific.

More deep dives, please! These videos are presented very well.

Keep the deep dives coming! Your RU-vid platform is unique. You cover a given topic first at higher level then more deeply in subsequent episodes. That maximizes your audience reach and allows users to customize their 'curriculum'. Really enjoy your books and Teaching Company DVDs.

This is one of my the most favorite channels! Please, more deep dives!

Love the deep dives. Keep them coming please. Thanks!

Deep dive is fantastic, please do more! Love actually gettiing to *LOOK* at a topic instead of just glossing over it.

This format was great! More please 🙂

Wonderful as always, Dr. Lincoln!

More deep dives, please. You provide so much insight.

Excellent video. Deep dives at this level of detail are just what I need. Thanks and keep 'em coming.

Thank you, Don, Kirsty and Fermilab for making these videos! I’ve watched them all over the last year and am left with many questions for your consideration: 1) What would happen if the slits of the double slit experiment were solid matter, but transparent, like glass? The photon interacts with the wave of the electrons in the glass, slowing the photon down, but is that enough to collapse the wavefunction of the photon? 2) Light is observed to move at the same speed regardless of the speed of the observer. Does this still apply when light slows down in a medium? Can light have a proper time if it is not going the speed of light when it moves through a medium like glass or water? 3) Since space contains virtual particles (quantum foam), does this act like a medium (like water) so that light never actually moves at quite exactly the speed of light? 4) Light can have a mass if it is a force carrier of QED (from an episode called “Quantum Foam”). Do photons still travel at c if they have mass? 5) Do gluons squeeze quarks together from the outside rather than pull quarks together from in between? 6) Are gluons everywhere in the vacuum or just inside of atomic nuclei? 7) How do we know that the two orthogonal wave components of a photon are associated with the electrical force and the magnetic force respectively? 8) When a force carrier is exchanged between electrons, how does the force carrier know where the target is? Does this rely on the principle of least action? 9) If force carriers must be exchanged for particles to be directed around the loop of a particle accelerator, does this mean that the path of the particles is rather geometric like a Feynman diagram (straight lines and sharp angles that average to the curvature of the accelerator)? 10) Can force carrier photons be absorbed by our retina and register as light in our brains? 11) What happens when the quantum foam (a virtual particle) interacts with something real? How do virtual particles disappear after getting intimately involved with real matter and energy? 12) How does the universe know which particles are virtual and which ones are real so that it can erase the virtual ones? 13) Just as virtual particles can pop into existence and then disappear, can real particles disappear, so long as they return? 14) When particles are entangled, could they be connected in a higher dimension so that there is really no distance in the “spooky action at a distance”? 15) If electromagnetism has no range limit, and electromagnetism acts by exchange of photons, is every electron in every galaxy pushing on every other electron in every galaxy and all are constantly exchanging photons? 16) Why is it that when kinetic and potential energy (like quarks swirling around each other at near the speed of light or quarks/protons stuck together by the strong force) are confined to a small space, it acts like mass (attracted to other mass by gravity and has inertia)? Since relativistic mass is not real, why would concentrated energy exhibit the characteristics of mass? 17) I’ve heard that a hot cup of coffee weighs more than the same cup of coffee when it is cold. How could this be true without relativistic mass? 18) What is the pion condensate and what role does it play in the mass of the atomic nucleus? 19) If one extra matter particle is created for every billion or so matter/antimatter pairs, and matter/antimatter pairs can annihilate back into energy, could this back and forth between matter/antimatter and energy be a filtering process until there is only matter? 20) Does the Higgs field impart mass to antimatter? 21) Once we know if antimatter falls up or down, will we be able to say confidently if antimatter is attracted to antimatter via gravity in the same way that matter is attracted to matter? 22) When a top quark (172 billion eV) decays to a bottom quark (4.2 billion eV) and a W boson (80 billion eV), where does the rest of the mass (eV) go? Photon? 23) Is the number of neutrinos in the universe increasing dramatically over time? 24) Why does it follow that the ability of neutrinos to change their identity means they have mass? 25) Why is neutrino oscillation regular over distance? Is this process effected by relativity (length contraction)? 26) If gravity information (which moves at the same speed as light) takes 8 minutes to get to earth, shouldn’t earth be attracted to where the sun was (as it moves around the galaxy) 8 minutes ago? 27) If gravitons exist, would a -2 spin antigraviton be responsible for antigravity (accelerating expansion of the universe)? 28) If the universe is expanding only at the scale of superclusters of galaxies, does that mean that each supercluster or maybe smaller groupings will eventually collapse? In other words, what is preventing many small “big crunches” from occurring under the force of gravity? For example, expansion is not sufficient to prevent the Milky Way from colliding with Andromeda. 29) What is the longest possible wavelength of light? If the universe continues to expand, the CMB will redshift theoretically forever? 30) The universe is ~5% regular matter, 27% dark matter, 68% dark energy, but what about regular energy? Is it less than 1%? 31) What is the relationship (if any) between dark energy and quantum foam/virtual particles? 32) How do we know that dark energy became important only 5 billion years ago and what happened around 5 billion years ago that made it important? 33) We can use limits to see if light experiences time. Do we trust the use of limits to give us the correct answer to this question? 34) In episode “Relativity's key concept: Lorentz gamma”, the flashlight emits many photons in an arc of many angles around the business end of the flashlight. Which photons hit the mirror: the ones that leave the flashlight along the axis of the length of the flashlight, or the ones that leave the flashlight at some angle to the axis of the length of the flashlight? It seems like the answer would be different depending on the observer. 35) Regarding episode “Relativity's key concept: Lorentz gamma”, can we derive the Lorentz factor if the flashlight is turned in the same direction as the motion of the train? 36) Why is the speed of causality one particular speed and no other. Would the universe be very different if the speed of causality was 300000000 as opposed to 299792458 m/s? 37) Spacetime is curved near mass, but why does that make mass want to move? We can think of curved space time as a slope that things roll down, but the reason that things roll down a slope is gravity! The logic is circular. Why does mass care if spacetime is curved? Why can mass be at a lower potential energy by moving into a gravity well? 38) Are orbitals (1s, 2s, 2p, 3s, 3p, etc.) able to overlap without violating the Pauli exclusion principle because the electrons have different energies and are therefore not identical? 39) Why can’t an electron emit a photon, losing all kinetic energy, and fall into the nucleus just as it can emit a photon and fall from an exited state to the ground state? 40) In the double slit experiment the light goes through both slits because “it is a wave in addition to being a particle”, but the EM wavelength of light is always shown as being parallel to the direction that the photon is traveling. When talking about wave/particle duality in this case, does the wave refer to position of the photon as opposed to the EM wave? 41) Is there an uncertainty in the direction of a particle (like a photon) at t=0 when it is created, or does its position only become more uncertain the further it travels. Maybe both? 42) Can a photon be described as a particle, and two waves (energy and position), whereas an electron would be described as a particle and 4 waves (mass, charge, position, energy)?

Appreciate the deep dives, and it's helpful to list the more basic videos on the same topic, for background information.

Yes, thoroughly enjoyed this. I think deep dives into narrow topics are a good idea. You've done, and there are plenty out there, broader videos and there's only so many of them worth making

Yes Jedi Don, please do so, more deep observations! Many thanks!

I really think many more of these deep dive videos are great and needed. Truthfully I would do a mix of videos that give a general overview and then a follow up deep dive video on the subject in question. Just my thoughts. Great job as always!

Loving the deep dives! This finally answers a handful of questions I had about the fundamental forces.

Thank you for the vid! That was as clear as it can get. Would very much appreciate more of that level.

Dive deeper - that’s why I follow this great channel - keep up the good work 😊

Thanks for this brilliant video! I’d love to see more deep dives!

Yes, more deep dives are very welcome!!! Thank you for your great work.

More deep dives please! This was an awesome video!

Don presents the absolute best videos on physics. More deep dives to stretch my mind even further, please! So far beyond what I can understand but I typically get a nugget from each. Not unlike my reading and re-reading A Brief History of Time probably 50 or 60 times in the last 15 years. I gain more understanding with each reading as time goes on.

yes please, love the deeper dives. You're a talented communicator Don, very enjoyable.

More deep dive! thanks for sharing!

More deep dives please! Thank you this video was great

thank you for the deep dive, the level of detail was just enough for me to understand easily with some thought put into it

I love this video style! Getting into nuance in any capacity makes these types of videos more interesting

Great work! More deep dives please!

That was a great video which enlightened this topic. More deep dives please!

Love the deep dives, sir.

Loved this one, more deep dives please!

deep dives are greatly appreciated, thanks!

Please! Please! Please! More and more of these in-depht videos! Greeeeeeatly appreviated.

Both are good. Mix deep and shallow dives man! You are great doing any! Thanks

Loved the video, would love to see a longer form with more info and comparisons.

Easyly one of the best videos you ever made! Thank you very much!!!

This answered questions that I've had for quite a while. Thanks - deep dives get my vote!

Verry interesting!! I always learn from ya!!! More deep dives please!!!:)

Great stuff, Dr. Don! ❤❤

Definitely a deeper dive. That was awesome!

Loved this deep dive. Please make more

This may be my favorite video! I would love more of the in depth videos. RU-vid already has a lot of surface level videos. Deep dive as deep as possible! Thanks!

More please! I feel like I actually learned something for the first time in a long time. Or, at least seriously challenged my rudimentary understanding. I didn’t understand weak force before, still don’t, but now it feels like there is something more I can learn.

Very intelligent comparisons. Thank you!

I really liked this take on the relative strength of forces - I had never heard this before! Would love to hear more explanations like this. Thanks!

Great format, and subject matter. I would love to see more content, in a similar format.

Deep dives are great! It’s not often I find like a 2 hour long lecture on some scientific topic but it’s always a pleasure to watch them

More deep dive please. This was excellent.

I enjoyed the level of detail in this one, I like deeper dives for sure!

Please please do like a series of videos on this rabbit hole! You are one of the more knowledgeable persons in this topic on youtube, and basically everyone else only touches surface level stuff. I would adore if you delved in the rabbit hole mentioned at the end. This video was kinda mind blowing and now I wanna learn more about the four forces

Brilliant. Thank you. More deep dives please

Deep dive is awesome! Please do it more 🎉

Love the deep dives, more please

Just do it all. Initial broad strokes video and then circle around to the deep dive. Love the vids!

Deep dives, please. Thanks for your great work.

Loved this. Deep dives are great!

More deep dive for sure. I've heard the same videos about QM a dozen of times. It is this type of content that gets me curious to do my own research on the topic

Please do more of these!

Details are fun and you do a great job of explaining them

This was awesome. Super informative and interesting

We love you Dr Don ❤, your expert explanations and style! Because phisic's everything...

Thanks for the clarifications!

The deep dive was great. thanks!

Love the deep dive. More please

Please more dive deep! We really are capable of handle them, you're a fantastic teacher! 😊

Deep dives are great, especially when you can link back to broader concept videos upon which one can construct a foundation for understanding. You’ve established quite a library for such development. Go for it!

This video was incredibly interesting. I would definitely love to watch more deep dive videos. Because, physics is everything

Please more deep dives!

Really great explanation And great presentation

These deep dives are really cool. Definitely more of them. I would love a more in depth discussion on the electroweak force, for example

The deep dive broadens understanding. More, please!

Deep dives are fantastic. I would love to hear more.

Amazing explanation. We want more deep dives please!

Really enjoyed this. Thank you!

More and deeper dives please!

Dr Don, I thought this was very interesting. I appreciate the 'deep dive'. More like this would be welcomed.