Chapter 392: Chapter 210 History Took a Turn Here (Still 10,000 Words!!)_5

As the light shone, a bright spot actually appeared in the center of the disk’s shadow!

And this bright spot was called the "Poisson’s bright spot," becoming the biggest face-slapping event in the history of science.

Poisson, a strong supporter of the particle theory of light, personally dismantled the theory in front of countless peers at the most famous conference venue of the time.

Since then, the wave theory of light has prevailed, and the particle theory of light has crumbled.

The particle theory only regained some face when Einstein was born, but by then, the theory of light particles was completely different from the initial particle theory.

Thus, this was a small personal motive of Xu Yun’s.

Rather than letting others in future generations overturn the particle theory, it’s better to let Little Niu discover the problem himself.

Of course.

From a nature perspective.

Marius’ polarization experiment might be more appropriate.

After all, it proved transverse waves, which neither confirmed nor denied the particle theory or the wave theory, occupying a very neutral position.

But Little Niu had already successfully demonstrated the particle theory using dispersion phenomena earlier, so compared to Marius’ polarization experiment, Poisson’s bright spot was undoubtedly more impactful.

No way around it.

Xu Yun did not know what situation Little Niu was facing, so he had to choose a strong dose, right?

A few minutes later.

After reading Xu Yun’s letter, Little Niu immediately began preparing various equipment.

Although the technology level of 1672 was not as advanced as 1818, the equipment requirements for Poisson’s bright spot were actually very complex.

But the University of Cambridge, being the world’s leading academic hub, found it not difficult to gather the required conditions.

Two hours later.

Everything was ready.

Little Niu drew all the curtains, approached the operation table, and officially began the experiment.

Little Niu used a light source derived from a composite prism, with the diameter and distance of the disk also optimally chosen — the latter being the reason it took him two hours to prepare.

Whsh—

The light source shone on the disk, and rapidly formed a projection.

Little Niu quickly walked to the edge of the projection, observing with a complex emotion.

A moment later.

Little Niu slowly walked to the desk, pulled out the chair, and sat down.

A few seconds later.

A soft sigh echoed in the room...

And, through the light source in the room, it became visible that there was indeed a small...

Spot of light in the shadow of the disk.

The wave theory of light, likewise, stood.

.....

In summary.

With the delivery of this letter, and the appearance of the light spot.

This already altered world line of history took another turn in an unknown direction.....

Of course.

At that time, Xu Yun did not understand what he brought to that world, nor did he know what impact this letter would have on him.

He only chose to exit the space after noticing nothing from the Halo Space following the disappearance of the letter.

"Hmm?"

After returning to reality.

Xu Yun instinctively pulled out his phone to check how long he had stayed in the space and whether he might have missed any calls.

However, once the screen lit up, he found the time on the phone unchanged from when he entered the space — at least, the minute hand was so.

In other words.

He had spent more than half an hour in the space, yet not even a minute had passed in reality.

This seemed a bit strange.

Over the past ten years, Xu Yun had entered the Halo Space many times.

He could be 100% sure that outside of the Dungeon missions and within the one-hour Northern Song Space-Time album, the passage of time in the space was completely consistent with the outside world.

Otherwise, he wouldn’t have deliberately run to the booth in the restroom.

Thinking of this.

Xu Yun couldn’t help but touch his chin, ponderingly:

"So..."

"The event like the letter actually falls under the category of a ’mission’?"

"But in that case, what about the reward?"

Just as Xu Yun was pondering.

A light screen suddenly appeared in front of him again. 𝙛𝒓𝓮𝒆𝔀𝒆𝙗𝓷𝒐𝙫𝒆𝙡.𝒄𝓸𝓶

[Detected Wall-Facer completed a special random encounter, received one encounter reward].

[Reward generating...]

[Reward generated!]

[Reward name: Legacy of Cambridge]

[Note, this reward can only be activated for use after the Wall-Facer completes the fourth regular mission, the Wall-Facer can carry one extra person]

A moment later.

A hard invitation card appeared in Xu Yun’s hand.

Xu Yun opened it and found it was filled with English:

You are cordially invited

to a reception

for Time Travellers.

Hosted by

Professor Stephen Hawking

To be held at

The University of Cambridge

Gonville and Caius College

Trinity Street

Cambridge

Location: 52° 12’ 21"N, 0° 7’ 4.7"E

Time: 12:00 UT 06/28/2009

No RSVP required

[Reward status: Pending activation (2/4)]

.......

Note:

I have some very sad news to tell everyone, a friend of mine, the author of "Flying in My Aviation Era" and "Great Nation Ship" Anxi You has passed away, and I am quite in sorrow.

The promised ten thousand words tomorrow may have to be delayed a bit, it’s hard to accept this reality, really not in the mood to write.

The essay competition took diffraction as the topic, also has a bit of meaning to clear the name of our ancestor Huygens. At that time, Fresnel had just converted from a civil engineering to optics and had already started to show promise, and participated in this competition. Coincidentally, Fresnel had already considered this issue before the competition and believed that light was a wave exhibiting diffraction. At this appropriate moment, he submitted early, waiting for the expert review committee’s verdict. The chief expert of this review committee was the renowned Poisson.