at glance

  • Keynote and Invited Presentations
  • Industrial Presentation by Fastlite by Amplitude
  • Regular and Poster Sessions
  • Panel Discussion
  • Exhibition

Panel Discussion

Comparing Ablative and Pure Photon Propulsion

Moderator: Dr. Claude Phipps,

Managing partner, Photonic Associates LLC, Santa Fe, NM, USA


1. Prof. Eniko Gyorgy,

Institut de Ciència de Materials de Barcelona (Barcelona, Spain)

2. Prof. Gediminas Raciukaitis,

Center for Physical Sciences and Technology, (Vilnius, Lithuania)

3. Dr. Maria Garcia del Piño, EducaMadrid (Madrid, Spain)

In this panel, we will discuss relativistic propulsion using just pure light pressure without ablation as in the “Breakthrough Starshot” proposal. This is the way in which humans (or instruments) can travel at relativistic speeds to explore regions within a few light years of Earth.

We will discuss specific limits to human relativistic travel including financial limits [for example, $20M/kg], psychological and emotional limits [returning to earth after 200 years], physical range limits even at relativistic speeds [probably 15 years in onboard time], and electrical energy limits. These, in my view, lead to using relativistic robots rather than humans. Even for these, the investment can be quite large [8B$ for Breakthrough Starshot, to accelerate a 1 gram payload to 0.2c].

Finally we discuss the unlikelihood of encountering intelligent extraterrestrial life in a search of space within 100 light years. For example, what if any society which has advanced enough to create thermonuclear bombs only endures 200 years before it self-destructs?

• What will be the effects of broadened horizons due to relativistic travel on human culture? Will it be like the discovery of the “New World”?

• If we find that we really are alone in this part of the universe, will this knowledge cause psychological problems?

• On the other hand, what if our relativistic vehicles bring us unwanted attention? • How do we handle the danger of relativistic flying objects with kinetic energy density greater than a thermonuclear explosion [30 times greater when v/c=0.99]?

• On the positive side, we on Earth can gather [some of] our tribe together and move tens of light years away if conditions on Earth become sufficiently bad in 500 years. Who gets left behind?

Social Programme:

Welcome Cocktail

14 May 2024 (20:00-21:30)

The Welcome Cocktail will take place in the Melia Palma Marina Hotel in Marina Hall. Do not miss this opportunity to say the first "hello" to attendees and committee members.

Gala Dinner

16 May 2024 (20:00-23:30)

The Gala Dinner will take place in the the Melia Palma Marina Hotel,
Conference Room Melia Meeting 8

Conference Programme

The detailed Conference Programme in the Acrobat (pdf) format (1.86 Mb) is available for download <here>.