Maoyuu Maou Yuusha - Volume 4 Chapter 1, “The Rainbow is Dipping.”

Why is the book Evolution Chart related to the theory of evolution?What is the relationship between the Ethereal Cloud Sword and the probability density?How did cultivators build atomic bombs?How did quantum mechanics appear in a cultivation world? Why were the ancient supreme experts and the modern ring grandpa labeled as being misguided and useless?What is the connection between Quantum Grandmaster, Daoist Proscribe, and Supreme Lord with the great scientists Bohr, Heisenberg, and Einstein?Let us follow the host, no, the protagonist Wang Qi, entering a world like never before and explore the secrets of scientific cultivation.

A scientific genius named Thomas Harrier was transmigrated to an imperial prince body after a car accident that took his life. He found out that he is in a world similar to our own with a timeline akin to early twentieth century. The body that he is occupying was the imperial prince of a failing empire who suddenly rose to power after a successful assassination attempt of his father. Unaware that the attack is just the beginning of what is to come. He faces many challenges throughout. Will Thomas Harrier be able to live his second life in peace while running an empire and getting it back to its former glory? Or will he succumb into a conspiracy lurking within the country's borders?

Expect some:

Cold war era techs.

Super battleship with advanced electronics, propulsion, and fire control systems?
Helicopters?
Missiles?
Modern medicines and equipment?
AC-130?
A nuke?
Challenger or Abrams or Leopard?
F-4 Phantom or MIG-21?
Colored TV's.

Everything!!!

PS. Cover not mine, I just found it on google.

Six months of continuous heavy rainfall has caused global floods.The Arctic glaciers melted, sea levels rose, and seawater flowed backward into rivers.Ancient viruses sealed in ice have been revived, leading to biological mutations and racial evolution.Everyone is trapped at home, unable to go outside.Liang Yuan unexpectedly awakens a Lottery System, which not only allows him to win various daily necessities but also different attributes.When everyone is struggling with a lack of food and clothing, Liang Yuan is enjoying steak, drinking red wine, and having a meat-filled diet every meal.A sexy and alluring neighbor, wearing a spaghetti strap bodycon dress, knocks on his door late at night: “Little brother, can you lend some food to your sister?”Liang Yuan: “Sis, isn't everyone short on food nowadays? Do you really just show up empty-handed to borrow food?”

The fat and ugly Nora Smith is the laughingstock of the town when her fiancé breaks off their engagement.He says, “The sight of your gigantic face and thunder thighs disgusts me! Don't ever pester me again!”“What an idiot.” Nora scoffs and turns around, her lips curling up into a smile.Later, when Nora successfully slims down, she returns as an astounding beauty.Her ex-fiancé comes to her bearing flowers and begs, “I was wrong, Nora. I’m willing to do anything as long as you come back to me.” Nora rests her chin in her hands and smiles as she replies, “Real men don’t dwell on the past.” Angered, he says, “You’re just a dimwit saddled with baggage that I dumped, Nora. No one will want you except me!”But following that…A young and popular singer tweets: “Nora Smith is my goddess!”An internationally renowned surgeon asks, “Are you free tonight, Nora?”Even the rich and influential hotshot whom everyone is scared of comes forward and says, ”I can take care of my wife and children myself, thank you very much.”