Cataclysmic Era: I can unlock the tech tree

"Citizens of the Human Union Dungeon No. 1183, according to the latest observations, the sun will unleash a helium flash in 30 minutes."

"Human civilization has entered its final 30-minute countdown."

"We...failed."

In an underground city 500 meters below the Earth's surface, a somber female voice plays from loudspeakers that can be seen everywhere.

Everyone who heard the broadcast felt an indescribable sense of suffocation deep within their hearts.

Lu Yongchang sat expressionlessly in front of a holographic projection.

In the holographic image, a giant fireball burns silently in the depths of space.

This is a picture of the sun at this very moment.

Lü Yongchang took a deep breath and waved his right hand in the air.

The holographic image was suddenly shrunk to show the full picture of the solar system today.

Unlike the previous solar system, this solar system now has two planets that have disappeared.

Venus and Mercury have been swallowed by the sun!

And the sun, too, has become a colossal, deep red behemoth!

In astronomy, it has a specific name.

Red Giant!

"Yongchang...Are we, no, humanity, going to perish like this?"

A slightly helpless female voice came from the side.

Lü Yongchang turned his head to look at his side.

A woman in a white coat sat in a chair, staring blankly at the holographic projection in front of her.

Lü Yongchang's eyes flickered slightly.

As the chief scientist of the Humanities Academy of Sciences, this woman named Su Yutong is his partner and his capable assistant.

"Yes, humanity is finished."

Lu Yongchang sighed softly and continued, "There are still more than twenty minutes left. Would you like to go down to the surface and take a look?"

Su Yutong's eyes flickered slightly as she turned her gaze away from the holographic projection in front of her and slowly stood up from her chair.

She reached out and untied her long, black hair, which was tied up in a bun, and faced Lü Yongchang, revealing a radiant smile.

"certainly."

……

Inside the elevator of Underground City 1183, Lü Yongchang and Su Yutong, both wearing heavy protective suits, looked at each other in silence.

The elevator screen continuously displays the current depth.

A hint of regret flashed in Lü Yongchang's eyes.

In 2045 AD, the sun, on which humanity depends for survival, will be affected by unknown factors, ending its prime and prematurely entering old age.

In just five years, the Sun entered the red giant phase, engulfing two planets in the solar system.

Driven to the brink of despair, humanity eliminated all barriers and formed the Human Federation, or simply the Federation.

Lü Yongchang, relying on his academic excellence since childhood, overcame all obstacles and successfully won the title of chief scientist of the Humanities Academy of Sciences!

In his calculations, even if the sun enters the red giant phase ahead of schedule, it will still take hundreds of years before a helium flash occurs.

Because the surface was no longer suitable for habitation, under his call, the Human Alliance built countless underground cities, and all of humanity entered the underground cities for refuge, while at the same time, they began to build interstellar spaceships.

But clearly, he miscalculated.

In just five years, the sun has traversed the lifespan of other stars that took billions of years!

A helium flash is about to occur!

Earth, as the planet currently closest to the sun, will undoubtedly be melted into a magma ball.

Human civilization has come to an end!

"Ding!"

"Dear Chief Scientist, I wish you a complete success in your research mission on Earth."

A crisp notification sound woke Lü Yongchang from his reverie.

He looked at the elevator screen.

518 ℃

This is the surface temperature outside.

The elevator doors slowly opened, and a wave of heat, accompanied by distorted air, rushed out!

Looking at the huge red giant star overhead and the scorching heat of the ground, even with the protective suit on, Lü Yongchang still felt a burning sensation!

"One minute until the helium flash occurs."

Su Yutong's slightly aloof voice came through the radio.

Lü Yongchang didn't speak, but simply raised his head and looked at the sun through the mask with filtering capabilities.

As the only advanced civilization on Earth, he did not want to bow down and face death!

"Do you know how much effort I put in to become your assistant?"

"Do you know why I did this?"

Perhaps because it was the very last moment, Su Yutong's voice was full of relief: "Because, I like you."

Lü Yongchang's pupils suddenly contracted.

A helium flash has occurred!

An intensely bright white light emanated from that red giant star and shone down upon the Earth!

In just a moment, Lü Yongchang lost consciousness.

……

A fluorescent green light filled my vision.

A white line slowly extends, drawing a tree-like diagram against a fluorescent green void background.

Lu Yongchang looked at everything in front of him with some confusion.

What... what is this?

A faint flash appeared at the bottom of the tree diagram.

Subconsciously, he turned his gaze to the bottom of the tree diagram.

Nuclear energy control: controlled nuclear fission.

A line of highlighted white text appeared.

The next moment, the white area began to extend upwards.

Nuclear energy control: controlled nuclear fusion.

As the previously dim text brightened, countless words and symbols instantly overwhelmed Lü Yongchang's consciousness!

……

"Lü Yongchang! Lü Yongchang!"

"Professor Guan is calling you! Lü Yongchang!"

In a daze, I heard familiar whispers calling my name from beside me.

The focus gradually became clear.

What came into view was a classroom.

Looking at the old man on the podium who was frowning and looking at him, Lü Yongchang's pupils shrank slightly.

Professor Guan Hualiang!

He...he passed away five years ago, didn't he?!

"Lü Yongchang! This is your first university physics class! If you dislike physics so much, why did you choose to major in physics?!"

Guan Hualiang's voice was tinged with anger.

Lu Yongchang looked bewildered, subconsciously stood up, and turned to look around.

A familiar scene.

This is... his university classroom!

If I remember correctly, this was his first physics class in his sophomore year!

He quickly took his phone out of his pocket and turned on the screen.

July 6, 2030!

Reborn...?!

In an instant, countless complex emotions surged through Lü Yongchang's mind.

Confusion, sadness, loss, and a glimmer of hope!

By the mandate of Heaven, may your life be long and prosperous.

This is the origin of his name.

As it turns out, the name was not a mistake.

In his previous life, he held the highest position among humankind, but... due to his mistakes, human civilization was completely wiped out.

In this life, he will make amends!

But... what should I do?

"Lü Yongchang! Did you hear me?!"

Professor Guan Hualiang on the podium was so angry that his face turned red.

In all his years of lecturing at Sandaokou University, he had never seen such a disrespectful student!

Lu Yongchang looked up at Professor Guan Hualiang on the podium and the blackboard behind him, his eyes flickering slightly.

Perhaps... he needs a chance to make a name for himself!

next moment!

The countless formulas and words brought by the fluorescent green tree diagram swirled in his mind like a storm!

P.S.: The plot in the first few chapters may have some flaws; this is also the author's first time writing a novel.

As for the female lead, she basically has no screen time; it can be said that there is no female lead at all.

Updated every night at 12 midnight.