The Cosmological Constant Problem Explained

The cosmological constant problem is one of the greatest problems in theoretical physics. This video looks at the problem from the perspective of changes in the effective description. Like and subscribe for more videos like this!

[michaelkahn]

Alternative Explanation of Dark Matter and Dark Energy
- 4-D Hypershere model of Universe can easily explain Dark Matter, Dark Energy, Void and even the reason why the measurement values of Expansion Rate are around 70 km/sec-Mpc

Dark Matter, Dark Energy, Gravity, Void and Antigravity, ... all these are same phenomena. They just look different.
The problem of modern physics is they're trying to explain everything with particle physics and the physics is being cornered more and more to the dead end. To escape the dead end, they invent or design another imaginary particle in vain instead of trying to revise their way to approach to the problem.

I agree to that idea that the interaction between mass and space must be explained with quantum mechanics.
But that doesn't mean gravity is the QM phenomena.
That's because gravity is not a force.
Dark Matter, Dark Energy, Gravity, Antigravity, Void... all these are just joint effects of the expansion of the Universe and the curvature of spacetime.
Details are given below.

Einstein’s theory of General Relativity states that spacetime is curved by the presence of mass.
This curvature influences the motion other objects with mass and gives rise to gravitation.
Thus, gravity is a result of geometric features in spacetime.
However, we also observe gravitational effects – curvature of spacetime – in areas without any detectable mass.
This has given rise to the concept of dark matter, which is matter that does not interact in any detectable way with normal matter, except through gravity.
So, there is some large quantity of dark matter scattered throughout the universe, which curves spacetime and causes gravitational effects just like normal matter, but we cannot see or detect it with any known method.

An alternative theory to the identity of dark matter is proposed – it is not matter at all, but rather an intrinsic curvature of spacetime.
In other words, spacetime is not naturally flat. Even in the absence of matter, we observe some inherent curvature of spacetime.

So, the question is now – why is spacetime naturally curved? Why is it not flat in the absence of mass?
The universe is 4-dimensional, with 3 spatial dimensions and one dimension in time.
Rather than consider time as a linear dimension, we can consider it as a radial one.
Therefore, rather than describing the universe with a Cartesian coordinate system, we describe it with a 4-dimensional spherical coordinate system – 3 angular coordinates, φ1, φ2, φ3, and one radial coordinate in time, t.
We live on the 3-dimensional surface of a 4-dimensional bubble which is expanding radially in time.
Thus, the Big Bang represents t=0, the beginning of time.
The crucial point is that the expansion of the universe is not homogeneous in all directions.

The expansion rate at one point on the bubble’s surface may differ slightly from another point near it.
The universe is only roughly spherical in 4 dimensions, the same way that the Earth is only roughly spherical in 3 dimensions.
The same way we observe local mountains and valleys on the surface of Earth, we observe local “mountains” and “valleys” on the surface of the universe bubble.
The inhomogeneity of the expansion of the universe has given rise to natural curvature of spacetime. This natural curvature causes the phenomenon of “dark matter”. “Valleys” in spacetime pull matter in, similarly to the warping of spacetime of massive objects.
So “dark matter” is really “valleys” in spacetime that are expanding slower than the regions surrounding it.
These valleys tend to pull matter in and create planets, stars, and galaxies – regions of space with higher-than-average densities of mass.
Conversely, “mountains” in spacetime will repel matter away, an “anti-gravitational” effect, which gives rise to cosmic voids in space where we observe no matter.
Each point on the surface of the universe bubble traces out a time arrow in 4-dimensional space, perpendicular to the surface.
These time arrows are not parallel to each other since the universe is not flat.
This causes points to have nonzero relative velocity away from each other.
It is generally accepted that the universe is expanding faster than observable energy can explain, and this is expansion is believe to be still accelerating.
The “missing” energy required to explain these observations has given rise to the theory of dark energy.
The time dilation caused by non-parallel time arrows can be proposed as an explanation for dark energy.

Alternatively, dark energy is real energy coming from potential energy gradients caused by non-parallel time arrows.
As a sanity check, we can calculate the expansion rate of the universe based on the universe bubble model.
Since the radius of the universe bubble is expanding at the speed of light in the time direction, it increases at 1 light second per second.
Therefore, the “circumference” of the 3-dimensional surface increases by 2π light seconds per second, or about 1.88*10^6 km/s.
This expansion is distributed equally across the 3-dimensional surface, so the actual observed expansion rate is proportional to the distance from the observer.

At present, the age of the universe is estimated to be 13.8 billion years, so the radius of the universe bubble is 13.8 billion light years, or about 4233 megaparsecs (3.26 million light years to 1 Mpc).

Thus, we can calculate the expansion rate of the universe, per megaparsec from the observer, as:

Expansion rate =

The popularly accepted empirical expansion rate is 73.5 +/- 2.5 km/s/Mpc, so our calculated value is close.
There may be some additional source of expansion (or observed red shift) to make up for the discrepancy. For example, if two adjacent points have some gravitational gradient due to non-parallel time arrows, then light passing through these points will be red-shifted.

[Itility_Peace_Of_Mind]

Hey Matt, just an arm chair barely understanding non-physicist, but is it possible the many constants we base physics on are not constant. One of the foundational assumptions of science is that physics doesn't change and is the same everywhere and except for first few moments of the big bang is the same in time, as well. Are any physicists now questioning these assumptions?

Perhaps they have changed as the universe matures and maybe not even constant throughout the universe. So what we observe and measure on a local scale (earth) doesn't hold true throughout the universe and throughout time. After all we have only been measuring things these constants for about 100 years.

I'm just glad when I wake up every morning yesterday's experience of the world is consistent with today's, assuming of course I'm not in a simulation and just programmed that way. 🙂.

[AbelShields]

Surely we can't just assume there's a particle at the Planck mass?
Aside from that, we have to directly measure fundamental constants such as G, the permissivity/permittivity of free space, even the speed of light (although with the new definition, really that's changing the definition of the meter - but I digress). When we get a new value for a constant, we need to update our theories and predictions. What's wrong with doing that with M? Why not have a "best guess" at the mass of the biggest particle and simply update our theories as we get more information, like the rest of science works?

[pecdo]

Where did you come up with "vacuum energy depends on the mass of the heaviest particle in nature to the power of 4", there is no paper or source that talks about it.

[aleksikoskinen]

bro im 15 and I just needed/wanted to know what the cosmological constant is for my physics project and now that I have watched this I have so many questions
good video tho

[jalpha]

Excellent work. Your video helped me understand the current astronomy crisis better, i would like to ask for your preferred set of bibliography to have a deeper insight into the math and technical concepts involved in the cosmological constant and its derivatives.

I would love to see more of your work explaining these kinds of problems in the future

[davidcarlson]

What causes the metric expansion of space quantified in the Hubble constant, and is H0 in any way related to the cosmological constant/dark energy? Secondly, what's the effect of the metric expansion of space on condensed objects, like Earth, and on orbiting objects like Neptune?

[Layeredworld]

The background music is really off putting

[gene]

well. seems to me that all those QED and QFTs are stitched together and not derived from deeper principles. A renormalization is a great tool, but still a tool only.

[or]

I try to combine the cosmological constant and the schrodinger solution on the planck scale.

I used planck units.

At the end I went back to SI units to compare with the measured vacuum energy density (0.63 10^-9 J/m^3.)

Combine:
1) Einstein, cosmological constant
2) Schrödinger solution
3) Planck units

Result:
- vacuum catastrophe solved?

1)Einstein, cosmological constant

Λ = (8π 𝐺 ƐΛ)/(𝑐^4)

Planck units:
G=1
c=1
Λ (6.1871424 10^34)^-2 = (8π ƐΛ [planckEnergy/planckVolume]

1.1056 10^-52 (6.1871424 10^34)^-2 = 8π ƐΛ

0.001149 10^-120 = ƐΛ

0.1149 10^-122/ ƐΛ = 1

2)Schrödinger solution, n=1

(ℎbar^2 𝑛^2 𝜋^2) / (2𝑚𝐿^2) = E

Planck units
hbar=1
n=1
m= mplanck =1
L= Lplanck=1
0.5 𝜋^2= E

1= E/0.5 𝜋^2


3)Einstein, Cosmological Constant = Schrödinger solution

0.1149 10^-122/ ƐΛ = 1 = E/0.5 𝜋^2

0.1149 10^-122 0.5 𝜋^2= ƐΛ Eplanck

Eplanck =1

0.1149 10^-122 0.5 𝜋^2= ƐΛ

0.567 10^-122 = ƐΛ [planckEnergy/planckVolume]

0.567 10^-122 1.9561 10^9 /(1.61625502 10^-35)^3= ƐΛ [J/m^3]

ƐΛ = 2.627 10^-9 [J/m^3]

Measured: 0.63 10^-9 [J/m^3]

I am looking forward to your response.

[Feroxing]

dude this is not for random guys looking for pop physics. too many equations.

[Toomanydays]

Couldn’t watch it after a few minutes due to the stupid music.

[ynwa]

Long winded way of saying nobody knows... As usual

[useruser-hkh]

Anything outside of addition, subtraction, multiplication, and division should be banned, as it has nothing to do with reality.

[evanpenny]

Doubtless brilliant, but it explains nothing. Sorry.

[LeMotMista]

That strumming guitar soundtrack is ghastly for this talk – distracting and inappropriate. Needs to be GONE. I'm off now to someone else's presentation on this subject, for there are many without the sappy elevator music.