The Universe (13.8 billion years) - unobservable (23 trillion ly.) and observable (46.5 billion ly.)

Beyond the visible universe, the invisible or the unobservable universe must be at least 23 trillion light years in diameter, and contain a volume of space that's over 15 million times as large as the volume we can observe. So that no signal can travel faster than light, hence there is a maximum distance beyond which nothing can be detected, as the signals could not have reached us yet. 

The visible universe is observable universe and it's physical limit created by the speed of light itself. This means a sphere with a radius of 13.7 billion light years centered around the Earth, and we can only observe 13.7 billion light years of the universe. Because the electromagnetic radiation from these objects has had time to reach the Solar System and Earth since the beginning of the cosmological expansion. The visible universe contains 4.9% ordinary matter (baryonic), 26.8% Dark matter and 68.3% Dark energy. Only five percent (5%) of the universe is visible and its radius is 46.5 billion light years.

Question on second LaGrange point (L2):

The Lagrange points are points of equilibrium for 'small mass objects' under the influence of two massive orbiting bodies. This means these points are positions in space where the gravitational forces of a two body system like the Sun and the Earth produce enhanced regions of attraction and repulsion. These can be used by spacecraft (here the Webb is in consideration) to reduce fuel consumption needed to remain in position. 

The James Webb Space Telescopes will orbit the sun 1.5 million kilometers away from the Earth, what is called the second Lagrange point or L2.The spacecraft will orbit Earth-sun Lagrange point 2, or L2.

L2 is a point located on the side opposite to the Sun, as it orbits the Sun. In this orbit, the Webb Telescope can maintain a safe distance from the bright light of the Sun, Earth, and Moon, while also maintaining its position relative to Earth.

See the image below where the Webb is located behind the Earth facing Sun.

#LaGrange #L2 #LaGrangePoint

Question-Answer session - questioning Time Dilation:

        Some Terreck Brian Franks Questioned: I am struggling to understand how time is either speeding up or slowing down, when in reality it seems like our "devices to measure time" are impacted by different forces; and these forces may alter our devices for measuring time even though they don't alter time or cause time to speed up or slow down. I honestly admit I do not understand this but I want to. I hear gravity makes time occur at a different speed, but a neighboring planet may have a different gravity - yet I don't see how time speeds up or slows down, even if a clock (device to measure time) may run twice as fast. Wouldn't we acknowledge that the change is the device and not actual passing of time. 🤦‍♀️ why doesn't this make sense to me... lol

QA Session :

Question (1): I am struggling to understand how time is either speeding up or slowing down.  

Responder:

At the outset, let me describe how time is defined through abstraction -

(i) "It is the indefinite continued progress of existence and events in the past, present, and future regarded as a whole, succeeds in irreversible succession."

The above is scientific definition of abstract time. Abstraction is a conceptual process (the quality of dealing with ideas rather than events.)

Abstract time is referred in the fourth dimension, above three spatial dimensions - the dimensions of height, depth, and width within which all things exist and move. Note that dimension is a measurable extent of a particular kind, such as length, breadth, depth, or height.

However, in physical applications, time is operationally defined as -
(ii) 'What a clock reads.' - This is real representation through a near approximation of the abstract time.

(A1) Therefore, since abstract time succeeds in irreversible succession, its progression either be speeding up or slowing down, are INVALID.

Moreover, from the abstract definition of time above, it is obvious that the existential events, within the Universe, are responsible to invoke conceptual time - which is progressing in irreversible succession, in the fourth dimension. In addition to that, though the existential events are real in space, but since the abstract time itself is conceptual, so it does not depend on real events, but those events can only invoke abstract time.

Furthermore, since operational time is real representation of the abstract time but no clock can read time - ideal to the abstract time, as the gravitational influence exerts mechanical stress on the clock oscillator depending upon the gravitational potential where a clock is.

Question (2): In reality it seems that our "devices to measure time" are impacted by different forces;

(A2) Certainly yes, as the clocks are subject to mechanical stress corresponding to the gravitational potential, so the oscillation of such measuring devices are impacted by the mechanical stress due to the gravitational force.   

Question (3): These forces may alter our devices for measuring time even though they don't alter time.

(A3) Yes, correctly said. The corresponding gravitational force influence oscillation of the clocks, resulting frequency of the clock oscillator lowered out of a gravitational well, correspondingly its wavelength enlarged resulting a greater reading in time, but such greater reading is not because of time dilated but because of the temporary error for the mechanical stress due to gravitational force on the clock oscillator. This is a phenomenon of Wavelength Dilation and not Time Dilation.

Question (4): I honestly admit I do not understand this but I want to.

(A4) By now, you have probably understood what is happening in the background as described in the (A3) above. You have raised this question in the very right direction. 

Question (5): I hear gravity makes time occur at a different speed, but a neighbouring planet may have a different gravity.

(A5) You are intelligent enough, and also in very correct direction in raising this question. It is obvious that the speed results displacement of a body so that the gravitational potential on that speeding body lowers as it speeds out of a gravitational well, correspondingly resulting lower gravitational potential that less-influence that speeding body, correspondingly its frequency lowers and wavelength increases resulting increased oscillation in the clock oscillator, so the clock reads greater time due to such temporary mechanical error. But when that speeding body passes besides a neighbouring planet/body, the above said processes reverses and the clock starts reading lower time than the time it was reading out of its originating source of gravitation well.  

Question (6): acknowledge that the change - is the device and not actual passing of time - doesn't this make sense to me:

(A6) by now you know how intelligent you are and also how correct your way of thinking is. Definitely, one day you are going to be a great scientist! I have enough reasons to admit that. 

Space and Time - the nature of relationship in their relation.

There is only abstract mathematical relationship between space and time, abstract relationship does not depend on reality, so time is independent from reality, existential events are real and also variable, and so there is the requirement of abstract, mathematical time.
However, time does not have interactable relationship with real events (so that events cannot interact with time) but events only invoke time, as time succeeds uniformly and irreversibly - according to its scale.
At the time of Einstein, Universe was not adequately known as it is known today, and so Einstein had to assume the universe as in a steady state, correspondingly infinite succession of time, but now we know that the universe is expanding and time has a beginning these makes Einstein's assumption about time and space was inadequate (This does not mean Einstein's discoveries were less important). Indeed Einstein's discoveries were remarkable but at the same time Einstein wrongfully interpreted character of time and space (those, now we now better).
Definition of time clearly transpires that real existential events invoke conceptual time, while time and space are dissimilar in characters, but there needs to be a mathematical relationship between events and time but not as in interactable relationship but abstract relationship (mathematical).

In a question of time dilation, time is represented on a mechanical clock:

Actually the real clock represents conceptual time within sixty uniformly-divisions of a clock dial having 360° circumference.

Now consider the case of time dilation, to accommodate dilated time, the uniformed divisions of seconds in the scale needs to be modified, but to accommodate dilated time within sixty uniformed divisions of second scale, a >360° dial circumference would be necessary, and this makes the concept of time dilation absurd. A dial can never be >360°.

Time dilation is actually wavelength dilation, in a relationship between λ∝T.  λ being real entity can be dilated but T being conceptual cannot be dilated but T would have corresponding mathematical values as per the dilated (modified) λ. Time dilation actually wavelength dilation.

#Time #TimeDilation #Clock