Is there life outside of our planet? Or are we, the Earthlings, alone in the entire Universe? Some say it’s obvious we’re not alone; others scorn at the very idea and still others will hauntingly report their own experiences of UFO sightings. 

So, which is it? 

Source: DailyTelegraph

While I leave you to decide which side you're on, here are some theories that point towards the idea that, maybe... just maybe, we're not alone in this vast Universe. 

1. This man has apparently figured out a way to talk to aliens.

Stephen Wolfram, a computer scientist, and physicist claimed that he has figured out a way to talk to aliens. Apparently, he has devised a coding software, called Mathematica, which was used by the makers of the Oscar-nominated sci-fi film "Arrival". 

According to him, one can communicate with almost anybody using the basic constructs of mathematics. You can read about his theory in detail on his blogpost.

Source: Blog.StephenWolfram

2. Radio signals from a distant galaxy have led to speculations about the existence of alien life.

The earth has repeatedly been receiving bursts of radio waves from a distant dwarf galaxy.  Presence of these Fast Radio Bursts - as they are called - indicate that we have been receiving radio signals from someone, somewhere, away from Earth. 

These radio signals have been observed in detail by the astronomers and have led to the speculations about the existence of alien life. Though their origin hasn't been traced so far, scientists believe that they are coming from outside the Milky Way galaxy.

Source: phys.org

3. Thanks to the Goldilocks Zone, scientists believe there are parts of the Universe that could foster life.

Scientists think every one in five or six planets might be habitable. Their theory is based on the presence of the Goldilocks zone where it is just the right temperature for liquid water to exist. And where there’s water, there can be life, which could mean we're not alone. 

Source: Futurism

4. A former British UFO investigator shared his first hand experiences about UFO sightings.

Nick Pope, a former British bureaucrat and a current 'UFO expert', claimed that there are people who watch our skies. During his stint as an UFO investigator in the Defence Ministry he was the incharge at the UFO desk until 2009, after which the department was discontinued. Apparently his work turned him into an UFO believer. His book, 'Open Skies, Closed Minds', talks about the firsthand experiences he's had about UFOs.

Source: DailyExpress

5. Former Canadian Defence Minister believes that humans have copied technological breakthroughs from aliens.

Paul Hellyer, former Canadian Defence Minister, believes that humans have copied many technological breakthroughs from the aliens. Microchips and fiber optics, for instance, were taken off crashed alien vehicles and reverse-engineered. 

He also claims that the aliens have a special technology that would solve climate change as well, but they are hiding it from us.

Source: DailyExpress

6. NASA had once casually admitted they were in contact with aliens.

NASA, the federal agency that oversees the U.S. civilian space program, had casually admitted they were in contact with aliens. They even admitted that the aliens have a base on the far side of the moon, and are currently mining several planets in our solar system for minerals.

Source: YouTube

7. Scientists believe that crop circles are messages left by technologically advanced alien species trying to communicate with us.

In July 1996, one of the world's most complex and spectacular crop circles appeared in England. There is no doubt in the fact that these crop circles are real, but their origin remains a mystery till date. According to some scientists, these circles are messages left by technologically advanced alien species trying to communicate with us.

Source: YouTube

8. Popular UFO and alien sightings and abductions have been recorded.

Barney and Betty Hill’s abduction by the aliens

It was the first widely publicized report of an alien abduction. Barney and Betty Hill were an American couple who claimed they were abducted by extraterrestrials. 

Source: YouTube

The Foo Fighters

In the middle of World War II, American Air Force pilots reported seeing lights chasing their aircraft. These UFOs moved very fast and they were called 'Foo Fighters'.

Kenneth Arnold’s 'Flying Saucer'

Kenneth Arnold, an American pilot, claimed that he’d seen nine flat objects whip past Mount Rainier at speeds of around 1,760 miles per hour. 

Phoenix Lights

On March 13, 1997, thousands of people in southern Arizona saw weird lights move across the night sky. 

Do they or do they not exist? 

It's like Mulder from The X-Files says: 

The truth is out there... if you really want to believe.