Different people have different opinions. However, the question of hot jupiters ejecting terrestrial placed planets is dependent on when the hot jupiter forms and how quickly it migrates closer to its star through the stellar disk. If the migration occurs during the first million years or so, the planetary disk, planetesimals have time to reform. If later, well hasta lavista baby!
http://casa.colorado.edu/~raymonsn/hotjup.pdf
"The survival rate of terrestrial planets depends on the rate of migration (faster migration means higher survival rate) and ranges from 15–40% (Mandell and Sigurdsson, 2003)." and "Only a very small fraction (1–4%) of terrestrial planets survive the migration event without significant alteration to their orbits."
Umm, Umm and thrice Umm...
Why do you cite this paper? It strongly supports the idea that earth-like planets can form in the presence of a hot jupiter, which, I understand, you do not believe. Look at its conclusions:
"..based on the above arguments, we expect that terrestrial planets
can form in a standard bottom-up fashion in the presence of a hot jupiter, and survive for the lifetime of the parent star...
We have argued that terrestrial planets can form in the presence of hot jupiters. we have shown that potentially habitable planets can form in such conditions. ...
...we suggest that stars with hot jupiters may be a good place to look for extra-solar terrestrial planets....Our result, that potentially habitable planets
can exist around stars with hot jupiters, effectively widens the Galactic Habitable Zone...."
The background to these papers is that there is a bit of a problem seeing how earth-like planets can form. When a disc of material round a sun solidifies, there should be a lot of iron in the earth-type orbits, then rock, and all the gas and water should be further out. So an earth-position planet should be mainly made of iron.
If a giant planet from further out migrates inwards, and eventually falls into the star, this migration will stir up the ingredients. Specifically, it will bring water and gas inwards and eject some of the internal iron. So you end up with earth-type habitable planets, made of a mix of iron, rock, gas and water, in a liquid-water zone.
All large planets eject mass from a system. That is not an issue. In fact, outer gas giants eject more mass. From your paper:
"An outer giant planet ejects approximately one half of the total terrestrial mass in the system, while a hot jupiter can remove up to one third of the total mass."
What matters is the mix of materials left. You will note that the paper I cited earlier suggested that our solar system might have experienced an earlier migrating giant planet, a suggestion which this paper also supports. In fact, migrating gas giants may be the norm, and it may be that habitable planets composed of an iron core with a rocky outside and water on the surface can only form in this way.
So, in any event, the end result is a system that doesnt resemble ours.
as I've said before, the evidence mounts almost daily, that our solar system isnt the norm. Kepler should find many terrestrial sized planets but, although early in its mission, the suggestion is that of a lot of further planets found, the small ones are very close to their star.
The paper you have cited is in agreement with Mandell, Raymond and Sigurdsson (2007) (
http://iopscience.iop.org/0004-637X/660/1/823/70644.text.html ) which says:
"If planetary systems that suffer the migration of a gas giant to small distances can eventually form terrestrial planets similar to those in our own system, and the migration of young giant planets is a common result of interactions with the gaseous disk, then it is appropriate to consider the possibility that our own planetary system could have formed earlier generations of giant planets prior to those in the outer solar system.
It is early days yet, as I have often said, but it looks to me as if the migrating hot jupiter theory provides a good explanation of how inner habitable planets can be formed, and may well be the norm for our kind of system....