Yep…, we are alone… The only ‘advanced species’ in the universe are human beings. Or?
3D is the dimension we can see with our eyes. What about the dimensions not observable by our five senses? What about higher consciousness realities? Just remember that we humans can also see and hear only a tiny spectrum of the existing sound and light wavelengths.
Image source: 1) updated Solar System: illustrator unknown; 2) Solar System Modell: NASA/JPL; 3) The observable Universe: wikipedia; 4) National Science Foundation;